Do NY Islanders have cause for concern? (Trending Topics)

For a team fighting for playoff position, losing a starting goaltender for the final month of the season and beyond is often a death sentence.

So for the New York Islanders to lose Jaroslav Halak for six to eight weeks might seem to be a death sentence. And for any other team, it might be. The Isles ended Wednesday night two points back of the New York Rangers (with two games in hand) but comfortably up six on Pittsburgh. Basically, they're playing the Rangers in the first round of the playoffs unless Pittsburgh gets unbelievably hot and they simultaneously drop off a cliff. The question is how they get there.

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The loss of Halak obviously opens up the door for the starters' role to be given over to kinda-sorta backup Thomas Greiss, who has started nine fewer games but has a save percentage of .929 versus Halak's .919. Further, Greiss has only lost six games in regulation, largely because the Islanders have scored more goals per game in his starts than they have for Halak. Goal support isn't something over which a goaltender has any control, obviously, but you can't argue with a guy who's pushing .930 and has points in 22 of 28 decisions.

Or can you?

No question that Greiss has played out of his mind this season, but he is historically not this good of a goaltender. He's already surpassed his career high for appearances, and he's likely to blow that number out of the water now. The Islanders will almost certainly use him in every game for the rest of the year that's not a back-to-back, and the more exposure you get to a 30-year-old goalie with a .913 career save percentage prior to this season, the more likely he is to play that way going forward. That is to say that he faced some 2,200 shots at the NHL level in 89 games across six seasons. He is what he is: An average NHL goaltender who has never seized a starting job. That's fine. You need guys like that in the league.

But the overarching issue for both him and the Islanders is a simple one: Can he handle the bigger role?

While “workload” is something you hear about a lot in hockey, that's usually reserved for criticism of starting goalies who appear in 65-plus games in a season. There's no real evidence that this kind of extra work diminishes their in-season performance in any way, but it probably does wear on them physically nonetheless. You never hear about it when a starting goalie gets hurt late in a season and you can basically pencil in as many as 40-plus appearances for a guy who never played more than 25 times (with Phoenix in 2013-14) before this year.

The Islanders have 17 games left, four of which are the second end of back-to-backs, meaning that Greiss will probably play 13 or maybe 14 more games this season, depending upon team need. That would bump him to 43 or 44 for the year. It's a lot of work, about 50 percent of what he's done in his entire career to this point.

But again, we have a good idea of what Greiss “is” at this point. All the game data plus his age paint a pretty clear picture that this is, again, an average NHL goalie. He's not a .940 goalie at 5-on-5, simply put. This isn't even a Steve Mason case, where a netminder clearly benefited immensely from a change of scenery from dismal (Columbus) to drab (Philadelphia). His career number is .927, which is a little better than the league average, but if you adjust for shot quality it drops to .926, and then you have to also keep in mind that, hey, as a backup he's mostly going to be playing worse teams than his starters. All of which tells you a lot.

He's just on an unbelievable hot streak so far this year. How hot? This stretch of .940 at full strength over 30 appearances has been matched or surpassed in only six other 30-game segments in his career, all of which are either clustered around this portion of his current season and a run of nearly .942 from April 9, 2013 to Nov. 11, 2014.

This level of play is an uncommon occurrence for just about any goaltender, but for Greiss it barely ever happens. And what's interesting here is the near-immediate drop-off in play back toward career norms, or even a little below them, once he wrapped up that initial impressive run in 2013-14.

But that crash-and-burn scenario really shouldn't be that much of a concern, really, because as you expand from 30-game segments to 42-game segments in his career, Greiss becomes far more reliably average. The range of performance shrinks from 18 points (.924 to .942) to 13 (.923 to .935). If he can reliably deliver even a .931 save percentage at full strength for the bulk of the season, which would require him to take a big step back at this point, that's very, very valuable for the Islanders. It's well above Halak's numbers for both his career (.924), either of his seasons with the Islanders (.9218 and .9229), and any season he's enjoyed since 2011-12.

In fact, these numbers suggest that over his last 43 games, Greiss has been right in line with his career averages, but needed this big bump in improvement to get there. Which should be pretty telling as to his performance for the rest of the year. Of course, anything can happen. These are only averages and so on, and he could continue to play great. He even could get better. Of course, the greater likelihood is that he regresses as he has before, but you just never know.

So basically, I would not expect that the Islanders are going to suffer greatly without Halak for any length of time. Greiss is nothing if not reliably good in a limited role, and asking him to play another baker's dozen or so games theoretically shouldn't be the last straw that's going to cause him to collapse in on himself like a dying star. He hasn't been injured since 2013, and that seems to have been the only injury he picked up in his NHL career apart from a case of the mumps last season. So that's not a concern either.

But again, if you buy that workload is physically taxing, playing 40-plus for Brooklyn would, proportionally, be about the same as a starter who never cleared 45 games being asked to play 77. Not exactly easy, but these are top-level athletes. He should be fine. So should the Islanders.

They just better hope that goal support holds up when they play the Rangers in the first round, because neither Greiss nor Halak nor anyone else seems particularly likely to out-duel Henrik Lundqvist in a seven-game series.

Ryan Lambert is a Puck Daddy columnist. His email is here and his Twitter is here.

All stats via War on Ice unless otherwise stated

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