September 30 2011 09:27AM
Confused as to why Aaron Rome gets so many minutes? Check your spread-sheet.
In the summer of 2010, Mike Gillis and the Vancouver Canucks had a big decision to make. After finishing tied for 11th in the National Hockey League in goals against, the Canucks needed to find away to improve that aspect of their game. While they had strong defenders in Alexander Edler and Kevin Bieksa, along with an eventual Selke Trophy winner Ryan Kesler up front, what the team lacked defensively was the difference between being a "good" team and a "great" team.
Welcome to Moneypuck. It's a problem faced by many General Managers across the National Hockey League, but fully solved by few: What's the best way to affordably cut down on the amount of goals your team has scored against you? A few statheads who dwell for long hours over spreadsheets will tell you an efficient way is to deal for forwards who have high Corsi numbers with a consistent ability to play difficult minutes. Whatever that means.
In the case of the Vancouver Canucks, they went after a centre from San Jose named Manny Malhotra. Malhotra played relatively tough competition and even started the majority of his shifts (45.3%) in the defensive zone. On top of this, Manny Malhotra held a positive shot differential, which we'll express here as a "Corsi" rating, an expanded +/- measure which counts not just goal differential against a player, but shots, missed shots and blocked shots as well.
Simply put, the Canucks knew what they were getting when they signed Malhotra to a 3-year, $7.5M deal. He would play third line centre, eat up the most difficult minutes for the Canucks in 2011, and even escaped with a positive goal differential - He was on the ice for 2.29 goals for for per 60 minutes to just 1.68 for the opposition - an amazing increase from what the Canucks got out of Ryan Johnson the previous season.
Some moves the Canucks have made over the past year seem to have been made right off the pages of BehindTheNet.ca, a statistics website compiled by Gabriel Desjardins which tracks a host of obscure numbers straight from game recaps on NHL.com. Some of the numbers include the Corsi rating, quality of competition and where a player started and ended each shift. In fact, a number of personnel moves also have their hands all over the page.
Consider, for instance, Aaron Rome, against Keith Ballard. Ballard, despite coming off three strong seasons since the beginning of the "Behind The Net" era, spent time on the bench in the latter half of last season in favour of the underpriced sixth defenseman Rome. Though Ballard was earning earning $4.2M last season, he never fit in with the Canucks in a top four role. His offensive instincts, which would be wasted as a depth defenseman, were instead subbed in for Rome, who drew the ire of many a Canuck fan online for neutral and offensive zone giveaways and unspectacular play.
But the important thing to consider is defense: Aaron Rome allowed just 54.52 "Corsi events against" (shots, misses and blocks) per 60 minutes last season, which was third on the team behind just Chris Tanev and Kevin Bieksa. Ballard, playing similar minutes, was two events "worse" than Rome. The important thing to consider isn't Keith Ballard's superior offensive play, but that in the latter stages of a game, particularly playing with the lead, the Aaron Rome style of defense, low-event and low-excitement, is more beneficial to winning a hockey game.
Numerous factors went into Mike Gillis' overhaul of the Canucks' defensive unit last season. The addition of Malhotra, the regular spot given to Rome, along with the addition of Dan Hamhuis make it apparent that the Canucks are very aware of some of the more advanced metrics floating around the hockey blogosphere and the hockey world. Whether they take them from Behind The Net or from their own video analysis, the Canucks turned a fresh eye on defensive play this season.
Only one major roster change truly took place this past offseason: Christian Ehrhoff was traded away to the New York Islanders (or, his negotiation rights were) for a a dressing room door. Ehrhoff was consistently mediocre in his own end, and he'll be replaced quite by Alex Edler who is - by the numbers - more effective at both ends of the ice. The Behind The Net numbers give us an accurate indication of what actually took place with Ehrhoff on the ice and suffice to say, the Buffalo Sabres may not have made a wise investment.
Like a number of other teams mentioned in the James Mirtle article last week about the Moneypuck revolution, the Canucks are quietly making changes on their back end that could be made by a stat-geek blissfully checking over numbers in his basement. Casually looking over spreadsheets is not a way to build a hockey team, but it's a good supplement to the information provided to us by our eyes. Anytime the Canucks make a move, with team personnel or a trade, that looks suspect, it's best to check some of the numbers provided: Facts tend to betray our eyes and our biases towards certain teams or players.