Wednesday, December 17, 2008

Tim Thomas: How Long Will the Fairy Tale Last?

Tim Thomas has a .938 save percentage through his first 18 games. I am not one of those people who likes to trash Thomas and call him a fluke, because I think goaltending is a results business and style is more or less irrelevant (unless a goalie has a single, exploitable weakness or something like that). Breaking down a prospect's style will give you clues as to how likely they are to make it at the NHL level, but in my view a record of success at the pro level over multiple seasons trumps any negative scouting reports. Thomas may be a bit clumsy and awkward, but if he stops the puck then he stops the puck, and a career .916 save percentage suggests that he is no mediocre netminder. He also passes my standard litmus test, which is results compared to backups (2005-06 to present):

Thomas: 82-64-23, 2.70, .916
Backups: 44-48-15, 3.09, .897

Having said that, I don't think Thomas is a reincarnation of Dominik Hasek either, so how sustainable is that .938?

First off all, let's look at the backup goalie. Manny Fernandez is 9-2-1, 2.08, .924. I doubt Manny Fernandez is much better than average, so that suggests Boston has been very good in their own end this season. If we assume that Fernandez is really an average goalie (say, .910 or so) disguised by Boston's stalwart defence, then we can estimate the Bruins' shot quality against at about 15% better than average. Adjust Thomas' career average based on those results and you get .929.

Based on that estimate, it does seem reasonable that a strong year by Thomas could keep him up near .930 for the season. However, there are some warning signs:

1. The Bruins are leading a pretty charmed life right now, with all the percentages in their favour (11.5% shooting percentage, .933 team save percentage). Unfortunately, history has taught us that regression to the mean appears to be an unavoidable fact of life for hockey teams, and the smart money is that the Bruins will not continue either their scoring or save rates for too much longer.

2. Tim Thomas' penalty killing save percentage so far is .938. Needless to say that is leading the league. Thomas' ES save percentage is also very good (.941), but nobody can stop pucks at that rate forever when down a man. League average on the PK is usually around .870, and Thomas' PK save percentages for the last two seasons were .871 and .846. Maybe Boston has a particularly strong penalty kill this year, but I bet Thomas does no better than .900 on the PK, if even that, over the rest of the season, which would take some of the air out of his overall save percentage.

3. I don't think that 15% shot quality estimate accurately reflects Boston's defensive play. Julien is a good defensive coach, and the Bruins play a good team system, but that kind of shot quality would be elite. Fernandez has probably been either outperforming or lucky this season as well. Something like 5-10% better than average would probably be a more realistic estimate, which would suggest that Thomas should be closer to last year's .921 mark than somewhere above .930.

4. The Bruins are playing a soft schedule (Sagarin has them ranked 25th in schedule strength) in a weak division in the weaker conference. That's probably not likely to change much, but I just felt like pointing that out.

5. Thomas is facing 31.5 shots per game, compared to Fernandez' 27.3. I don't know if that is a statistical fluke or represents a real difference in on-ice play. Thomas has faced about 2 shots per game more than his backup goalies since the lockout, so he seems to be one of those types who have to make an extra save or two every game compared to average. If those shots represent more dangerous than normal chances (e.g. rebounds, turnovers, etc.) then he will be less likely to sustain a high save rate. For what it's worth, Hockey Numbers has Thomas facing more difficult shots than Fernandez so far.

Tim Thomas is not a fluke, but his season so far appears to be. I think it is probably fair to say Thomas is a good NHL starting goalie, but he looks like he is playing way over his head so far. I don't see his numbers going anywhere but down over the rest of the season.

Even if we expect him to cool off in the coming months, Tim Thomas does have that .938 and 1.96 GAA "in the bank" already, so to speak. If he regresses considerably over the next 52 games, he will still likely end up with some very good numbers this season. Let's say he plays 60% of Boston's minutes the rest of the way, faces the same number of shots per game (31.5), and stops 91.5% of them, which is probably pretty achievable given his career numbers and the team around him. His season numbers would then be 2.40, .924, which when combined with 30-35 wins and the injuries to Brodeur and Luongo could still put Thomas in contention for the postseason awards.

Thomas is an interesting case of a well-travelled guy who apparently had the light come on at the age of 29. In 2002-03 he was a journeyman AHLer (35 GP, .906), although he did show enough to get called up to play in 4 NHL games. Then out of nowhere came a huge AHL season in 2003-04 (.941 save percentage), a big year in Finland during the lockout (1.58 GAA), and then a season split between the AHL (.923) and NHL (.917) that finally solidified him at the NHL level. The late bloomer phenomenon is well-documented, and anybody who can find out just what makes these goalies suddenly put it all together will be able to command a very large salary from some grateful NHL organization.

4 comments:

Anonymous said...

In the late-bloomer category, Dwayne Roloson quickly comes to mind.--Brian Banker

Tom said...

The eyeball test (watching him play) tells me that Thomas is feeding off a very strong Bruins team. Basically it boils down to the two parts of the Bruins' game:

1) Defense - Boston catches a lot of flak for playing a trap game, but that's not why they win. They're frequently outshot, even by weak opponents. What makes the difference is that they drive opponents to the outside of the faceoff dots and allow shots from the point in order to block them. Typically Thomas doesn't see more than one or two breakaways, a handful of shots from the slot, and a couple of screened point-shots in a game. If he stops 80% of those difficult shots, he'll only let in a goal or two. And because the Bruins protect the slot, he is able to overplay the "easy" shots from the sides and points, knowing that he will get help from the backside (which is why he flops so often, jumping back into position after overcompensating). The odds in any game favor him allowing 1 or 2 goals and stopping 90%+ of the opponent's shots.

2) Offense - The Bruins have a great transition game and don't allow teams to overload the crease without risk of counterattack. Guys like Kessel and Savard force opponents to play at least one forward higher than the faceoff dots, which reduces the chance of a rebound opportunity. Also, the Bruins possess the puck fairly well and don't usually allow Thomas to get "shelled" for long periods of time.

Thomas is a very good goalie, don't get me wrong -- he has a nose for the puck, is extremely focused and flexible (yoga training!), and has a winner's attitude. But his numbers are largely a result of the defensive system that the Bruins have perfected under Julien, not some otherworldly ability that he's just discovered this season.

Bruce said...

Good post, CG, and excellent comment, Tom. I entirely agree that coaching, system, and team play should lead to differing expectations in Sv% from one team to another. This is why I am leery to accept Sv% as a be-all and end-all metric for goalies.

I know that somebody is working on "Expected Save Percentage" which is great, but I would lay money that any assumptions are flawed to some extent, as are the shot distance counts I understand they are based on, so the results while possibly helpful are not the be-all and end-all either. I would frankly put more value in an informed and informative observation such as yours over a stats model ... and I'm a stats guy.

pghblackandgold.com said...

I think Tim hit the nail on the head with the mention of Thomas's yoga training. If I'm not mistaken, he started that right around the time you said that the light came on. I don't think it's a coincidence.

I also don't think that means it would work for all goalies.