Should Preds fans be worried about Pekka Rinne?

Source: USA Today

It goes without saying that Pekka Rinne is central to the Nashville Predators' success in the upcoming playoffs, given his $7M cap hit on the Predators' $60M payroll and 93.66% 5v5 Save % this season. But something has been off with Rinne as of late, with Rinne posting a sub-.900 Save % in his last five consecutive starts. While Predators fans shouldn't point to momentum alone as a reason to be concerned with Rinne headed into the playoffs (e.g., Jonathan Quick's final two games last season were both sub-.900 Save % efforts), there has clearly been a drop-off in Rinne's play. In the below chart, I split Pekka Rinne's 2014-15 5v5 Save % (both regular and adjusted based on average shot distance) into two halves of the season - before and after his knee injury on January 15th. 

Data Source: War-on-Ice.com

Is fallout from Pekka Rinne's knee injury accounting for this recent falloff?  One could look to the unsustainable play of the Predators' skaters as a cause, but Rinne's Shots Against per 60 minutes (SA60) are nearly identical for both halves of the season (28.07 vs. 27.94). Something else is almost definitely explaining why Rinne's Save % has dropped nearly two full percentage points since returning from injury. 

Now, it should be noted that we are of course dealing with sample sizes here: 37 GP / 1,770 Min for the first half and 27 GP / 1,317 Min for the second half, respectively. It's probable that luck played some role in Rinne's early season success, and that Rinne has simply regressed back to the mean. Rinne is a career 92.87% 5v5 / 93.19% Adjusted Save % goalie dating back to 2008-09, his first full season in the league. If we boil that down to his relatively healthy 2008-09 through 2012-13 seasons, the numbers are a bit higher at 92.94% 5v5 / 93.36% Adj., as Rinne played just 24 games in his anomaly of a 2013-14 season. 

Source: War-on-Ice.com

So while Rinne's second half performance is much closer to his career average than his Vezina-worthy first half was, it's not crazy to infer that the knee injury is playing a part in Rinne's recent falloff. After all, Rinne is a butterfly style goaltender, a style that contributed to his needing hip surgery in the 2013 offseason and likely helped induce this year's knee injury given the connection between the hip and knee. Granted if you were to ask David Poile or Peter Laviolette about Rinne's health, they would tell you that the goaltender is just fine. In any case though, when trying to predict Nashville's ability to progress past the Blackhawks and beyond in this year's playoffs, we should expect Pekka Rinne's play to be closer to the second half version than the first partially due to both his career numbers and his recent injury history.

When digging deeper into Rinne's 2014-15 season, I was struck by how different one advanced metric was between the two halves. A trio of statistics recently introduced by War-on-Ice that I find intriguing is the separation of saves into high, medium and low percentage scoring areas as shown in the below graphic:

Source: War-On-Ice

When we compare the two halves of Rinne's in the below chart, it is glaringly obvious where Rinne's game has fallen off since returning from injury: Medium scoring areas. As mentioned previously, we are dealing with somewhat small sample sizes here. But when it comes to shots from the left, right and high slots and center point, Pekka Rinne is having a much harder time stopping these shots now than he was in the first half of the season:

Source: War-on-Ice.com

Now there is almost definitely some bad luck going on here when it comes to Rinne stopping Medium area shots; the question is how much? It is worth repeating that Rinne's workload has not changed too much from the first to second half of the season. The Preds continue to average around 28 SA60 and medium shot opportunities accounted for roughly one quarter of Rinne's workload in both halves of the season. As Rinne's a 93.58% Medium Save % goalie for his career, a little bit of regression was to be expected here; however, Rinne's second half is much further from his career average than the first with respect to Medium Save opportunities:

Source: War-on-Ice.com

While it's probable that Rinne's Medium Save % trends back upwards, it's worth noting that Rinne's only other season where he was this low in Medium Save % opportunities was last season's hip injury-riddled season. Furthermore, 2014-15 now ranks as Rinne's second worst season for Medium Save opportunities by a large margin after being on pace to be his best year in the statistic through 37 games. Compared to his peers, Rinne's overall Save % in the second half of the season still rates him along the lines of an average NHL goaltender such as Marc Andre Fleury or Jaroslav Halak. But among 33 goaltenders that played 1,300+ minutes this season, Ryan Miller was the only goaltender with a sub-.900% Medium Save %, placing the recent version of Rinne at the very low end of the playoff goaltending spectrum in that category.

So while we can't definitively link Rinne's drop in Medium Save % to his recent knee injury, it's worth exploring in future research whether a link can be established between lower body injuries and a drop-off in Medium Save % for goalies. In theory, medium opportunities could be where goaltender health and skill and most differentiable. After all, High Save % opportunities are largely based on goaltending fundamentals than differentiable goaltending skill and health, while Low Save % opportunities have a lot more luck involved due to the shot proximity. 

So how concerned should the Predators be? While there should be more room for optimism in Nashville than other markets due to the Laviolette-coached Predators' improved ability to drive possession through multi-shot shifts, the team should at best expect Rinne to play at his career averages. Perhaps that could be enough, as this year's Blackhawks only scored on 7.62% of shot attempts. However, Rinne's recent play (not to mention the probable return of Patrick Kane for Game 1) could very well help the Blackhawks regain their goal scoring clip of 9-10% from the previous five seasons. Whether it's a function of injury or not, Pekka Rinne's play will definitely be one of the top storylines to follow in the NHL's opening playoff rounds. 

Handicapping the 2016 NHL Entry Draft

Source: The Hockey News

From the first NHL Entry Draft Lottery in 1995 up until this summer's 2015 draft, the NHL's worst team in the league has been rewarded with the knowledge that they will either have the No. 1 or No. 2 pick in the upcoming NHL Entry Level Draft. Sure, the odds of winning No. 1 have gotten progressively worse in recent seasons. In 2013, the league removed the four spot maximum the lottery winner would jump up in the draft, nearly cutting Team 1's chances of winning the lottery in half. For 2015, the odds that the four worst teams in the NHL could win the draft lottery were reduced to further discourage tanking. However, there remains a 100% chance for 2015 that the worst team in the league will come away with a Top 2 pick, as the only chance that the 3rd through 14th worst teams in the league have to move into the Top 2 is by winning the lottery.

So despite the recent best efforts of the Arizona Coyotes and Edmonton Oilers to lose games, the Buffalo Sabres are potentially just 13 games away from securing the highest odds to select either Connor McDavid or Jack Eichel, two of the most celebrated prospects in recent NHL history. But the story of the Sabres' 2014-15 tank job in the pursuit of McDavid/Eichel has already been very well documented. This post looks at the Sabres of next year and beyond, and why the diminished returns of tanking starting in the 2015-16 season means the Sabres are geared to actively try winning games again next fall.

The new NHL draft lottery system

Buffalo is a city that is not used to catching many breaks in sports, as there is still plenty of time for the Sabres to overachieve and close the season in 29th place. But Sabres fans should nevertheless take comfort in the fact that the NHL delayed implementing its version of the NBA's draft lottery until 2016, when the top 3 spots in the draft are subject to a lottery as opposed to just the top pick. Take the draft classes of 2008 and 2009, for example. Though elite centers Steven Stamkos and John Tavares were drafted No. 1 overall in those respectable drafts, the No. 2 teams had the likes of Victor Hedman, Matt Duchene, Drew Doughty and Alex Pietrangelo to pick from in those drafts (not to mention recently acquired Sabres Evander Kane and Zach Bogosian).

Source: Lighthouse Hockey

The league made it well known last summer that, starting in the 2016, the worst team in the league is able to slide back as far as No. 4 in the draft as the NHL will hold three separate lotteries for the #1, #2 and #3 picks. The question is, how often should last place expect to win any of the three lotteries vs. sliding back to #4, and how much riskier does that uncertainty make it for teams to pursue a full scale, "tear it down" rebuild going forward? We can apply concepts from a probability mass function to calculate the odds the teams the NHL teams that miss the playoffs, ranked 1-14, have of winning a coveted 2016 draft position (1st, 2nd and 3rd) and contrast those odds with 2014 and 2015 - two years where the Sabres were constructed to pick at the top of the draft.

The #1 pick lottery

Source: NHL.com

As most fans are well aware of, the odds of winning first place were reduced from 2014 to 2015. The new first place odds will also apply to 2016, and presumably 2017 and beyond. However, it's conceivable that these odds end up being too low and tweaked again in the future if enough teams from the "field" end up winning the lotteries. The NBA set the precedent for this sort of chaos happening when the 1992 Orlando Magic won the rights to draft Shaquille O'Neal despite their 1.5% lottery odds, which would rank somewhere between a team like the Winnipeg Jets or San Jose Sharks winning the Connor McDavid sweepstakes this season.

But as far as Sabres fans are concerned, any team that finished last this season was going to have better odds of picking second than first. That scenario is now just more likely in 2015 than it was in 2013 draft, around the time when then-Sabres GM Darcy Regier made the decision to start "rebuilding". As far as Sabres fans should be concerned, winning the 2015 draft lottery would be gravy. What was most important about this draft was at least being able to draft second, where a prospect that would go #1 overall most other draft years would fall to #2.

The #2 pick lottery

To calculate the odds of winning the 2nd lottery draft for 2016, we have to consider that the abilities of each team winning the 2nd pick are affected on a "proportionate basis" by the team that won the 1st pick. For example, let's pretend that the 2012-14 Draft Lottery results reoccur in 2016 and the second worst team from the previous season wins the 1st lottery. As a result of Team 2's 13.5% odds being removed from the 2nd lottery, Team 1's chances of winning the #2 pick improve to 23.12% (i.e., 20% / (100% - 13.5%)). Alternatively, a "Shaq" scenario like Team 14 winning the lottery would only result in Team 1's 2nd lottery odds improving to 20.20%:

When we add up all scenarios for how often the worst team in the league wins the No. 2 pick and multiply them by the frequency that they are expected to occur, the odds of last place winning the No. 2 pick total up to 17.5%. Though it seems counter intuitive, this is largely due to the fact that the worst team in the league wins the #1 selection 20% of the time - meaning it only eligible to win the #2 selection 80% of the time. Teams 2 and 3 also have more scenarios where they draft first than second. Though team 4-13 have better odds of picking second than first, that is mostly because Teams 1 or 2 or 3 are expected to win the #1 lottery 45% of the time. Though Teams 1-3 have better odds of winning the lotteries than the "field" does, what makes the field potentially big winners of the new draft lottery system is that they now have three opportunities to move into the Top 3 of the draft versus just one.

The #3 pick lottery

The increased uncertainty of pursuing tanking as a team building strategy is reinforced in the above table, as the field continues to have a larger number of scenarios where they win a Top 3 pick at the expense of the dregs of the league. The new system is particularly bad for the worst two teams in the league, whose odds of securing a Top 3 are respectively reduced by 48.49% and 61.95% from this year to next - a scenario in 2015 that would remove the guarantee that 29th place, at worst, wins the rights to draft stud defenseman Noah Hanifin.

In total, the worst team in the league wins the #3 draft lottery in 15.02% of scenarios - a function of it winning the #1 or #2 pick 37.49% of the time as well as its low initial draft odds only slightly improving its win odds in the subsequent lotteries. Even when the 2nd and 3rd worst teams in the league win the Top 2 spots in the draft, the worst team can only expect to win 3rd place 26.67% of the time (i.e., 20% / (100% - 25%)):

Starting in 2016, last place can expect to fall back to #4 draft spot 47.49% of the time. If the 2016 system were in place for 2015, Sabres fans would be almost just as likely to agonize over which of Lawson Crouse or Dylan Strome they would rather see the Sabres draft as they would be to look forward to McDavid or Eichel (or Hanifin, for that matter) being at training camp in the fall.

Source: Buffalo Hockey Beat

Turning the page on the Sabres rebuild

The good news for Sabres fans tired of tanking is that the new draft odds should only further encourage Tim Murray to actively build a winning roster again. Two other main factors in the Sabres' favor against again tanking in 2015-16 include:

1) Competition for 30th place: Headed into tonight's St. Patrick's Day tilt vs. the Bruins, the 2014-15 Sabres are on pace to set new single season lows for puck possession (5v5 Corsi % of 37.1%) and goal differential (-101) in the NHL Salary Cap era. If the season were to end tonight, they would annihilate the 2013-14 Toronto Maple Leafs' 5v5 Corsi % of 42.8% and the 2013-14 Sabres' -91 goal differential marks. Despite these historically abysmal stats, the Sabres still only trail Edmonton and Arizona in the standings by 5 points - with a game in hand on both!

With the Arizona Coyotes and Toronto Maple Leafs potentially all in on rebuilds for next season, the Sabres could hypothetically try to tank again in 2015-16 and only come away with the third worst record. But as established in the above sections, the scenarios where 4th or 5th worst team end up picking in the Top 3 are only slightly worse than the 2nd and 3rd worst teams in the league, Tim Murray should turn his focus towards building a roster that can win hockey games. Perhaps the Sabres are a playoff team again in a few years, but they will be hard pressed as is to finish outside of the Top 5 next season.

2) They don't need to be last again. 2015 will mark the Sabres' third straight draft picking in the Top 10 of the 1st round, and 2016 will most likely make it four straight given the current state of the Sabres' defense. But because the key building blocks of the last few drafts - McDavid/Eichel, Reinhart, Ristolainen, Zadorov and Girgensons, just to name a few - will be locked into the organization, it is not imperative for Buffalo to get the best player possible as it is for the Sabres to properly develop the ones they already have. As it is, they are only slightly less likely to win a coveted draft position should they try to win games again next year than if they try to tank again.

Though GM quotes always need to be taken with a grain of salt, Tim Murray is on the record saying he doesn't plan to be bad again in 2016. Given the recent acquisition of Evander Kane and rumored interest the team has in a player of Ryan O'Reilly's caliber, Buffalo certainly appears to be serious trying to win again in 2015-16. In this own writer's opinion, the expected replacement of Andrej Meszaros and Andre Benoit on the blue line with two league average defensemen will alone be worth several points in the standings. Furthermore, this summer's goalie market is a buyers one, making the cost of upgrading the current goaltending tandem of Chad Johnson/Anders Lindback modest for a team with ample cap space like Buffalo should they choose to go that route.

For the foreseeable future, the NHL has allowed the Sabres to get away with the last "easy" rebuild in terms of accumulating top end talent. And whether it's McDavid or Eichel taking the ice at Sabres' training camp in September, fans can be confident that the team is actually trying to win again. The team will still be a couple season away from competing for a playoff spot - let alone a Stanley Cup - but the worst of the Sabres rebuild should be in the rear view mirror.