After last night's win against Minnesota, many wonder: is Pekka Rinne's new mask to blame for his struggles? But perhaps they should instead ask: is he struggling at all?
On paper, Pekka looks to be doing worse. His save percentage has dropped from last year's stellar .930 to .918--the first time it has been below .920 in recent memory. Fans have given a variety of the usual explanations: he's overworked, pressing, letting in too many soft goals.
A closer look at the numbers, however, shows his performance to be essentially identical to last season's, save for one aspect:
Pekka's doing a lot worse on the penalty kill. This struggle mirrors a general decline in the Preds' PK, which has fallen from 5th best last season to 10th worst currently. Many attribute the decline in the team's short-handed efforts to the lack of a physical crease-clearing defenseman, a la Shane O'Brien, but could Rinne really be at fault? Or is it a chicken-and-egg riddle in which the impact of O'Brien (and Joel Ward's) contributions can never be separated from Rinne's play?
It's hard to say, but either way, hardly surprising. Goalie talent seems to have little to do with penalty kill efficiency. On a year-to-year basis, the league average short-handed save percentage is more predictive of a goalie's SHS% than the number he put up last year:
Basically, Even-Strength save percentage, which is measured over a large number of shots, is a significant predictor of future performance, though it must be heavily-regressed to the mean save percentage. SH save percentage, on the other hand, is essentially random. Your best guess of next year's SH save percentage is the league average. - Gabriel Desjardins at Arctic Ice Hockey
It makes intuitive sense. Contrary to the cries of the Bridgestone faithful (shooot!), teams generally pass on the power play, favoring the highest percentage chance over a barrage of shots. When a shot is taken, that team risks changing possession and having the puck cleared, so they have incentive to to wait and shoot when the goalie is most helpless.
I mentioned this fact over the summer in my case for trading Pekka (so much for that), and predicted that his SHS% this season would be closer to the league average (.879) than his own (.912), ultimately bringing his save% closer to .920 than .930 for the season.
Ultimately, some bigger bodies on the PK might help Pekka. But the penalty killers aren't totally to blame. Rinne is still an elite goaltender, just not as lucky as he was last year.