But so far in 2010, Green is doing everything he can to prove his critics wrong.
Caps coach Bruce Boudreau is using Green in crucial situations and so far it's paying off. Green was on the ice in the final minutes of the Caps' 5-3 victory against the Boston Bruins on Saturday, helping to protect a precarious one-goal lead before Alexander Ovechkin salted it away with an empty-netter.
Green is plus-7 through 11 games this season, but his plus-39 in 75 games last season wasn't enough to get people off his back. This season has been a little different. He's been frequently matched up with the opposition's best scorers, which makes Green's plus/minus rating a little more impressive.
"I was asked to play more of a shut-down role and I'm taking pride in that," Green said. "In the past that wasn't my job and now it is. I take pride in what's asked of me."
"I was asked to play more of a shut-down role and I'm taking pride in that. In the past that wasn't my job and now it is. I take pride in what's asked of me." -- Mike Green
"You have to find a balance," Green said. "It's hard to find a balance at times, especially at the start of the season. It kind of takes some time to get the feel. But I've found that balance."
Capitals forward Mike Knuble is a little flabbergasted that Green still has to defend his defensive play.
"I guarantee you when we're in the last minute of the game, he's going to be out there," Knuble said. "If he was a defensive liability, he wouldn't be out there. I think he gets knocked a bit for his defense, but he's such a great skater. He's a fit guy, he's strong, he's got a really good stick. He's hard to play against.
"He came into the League as an offensive guy and probably that's what put him in the League. You check any penalty-killing situation, any key, crucial time when we need to keep a goal out, he's out there."
The numbers back up Knuble's argument.
Green is averaging 3:14 of shorthanded ice time per game this season, second on the team to fellow defenseman Jeff Schultz. Last season, Green was on the ice during shorthanded situations for an average of 2:09 per game, which ranked him fifth among Caps' defenseman.
The change is paying off in the early going for the Caps. They're ranked eighth in the League in penalty killing at 86.7 percent. Last season, when Green was on the ice far less during shorthanded situations, the Caps killed penalties at a dreadful 78.8 percent clip, ranking them 25th in the League.
Of course, one player can't account for the entire turnaround and this season is only a month old, but some of the credit has to go to Green's defensive play.
What's it going to take for skeptics to start believing in Green as a defensive defenseman?
"I don't know how long it's going to take for him to shake that," Knuble said. "Is it going to be a strong playoff run? I don't know what it's going to take for him to lose that stereotype. He's a great mobile defenseman and he's capable at both ends."
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