Griffin also chimed in. He did not appear in the locker room during the two hours it was open to reporters Monday morning, but he offered some thoughts on Twitter.
"Many may question, criticize & think they have all the right answers. But few have been in the line of fire in battle," Griffin tweeted.
The Redskins were expected to announce results of Griffin's MRI later Monday.
Already playing with a heavy black brace in his third game since spraining a lateral collateral ligament, Griffin hurt the knee again when he fell awkwardly while throwing a pass in the first quarter of Sunday's 24-14 playoff loss to the Seattle Seahawks.
Griffin stayed in the game, but he was far from his usual self, clearly favoring the knee and unable to run with the world-class speed that helped define his play early in the season.
Then, in the fourth quarter with the Redskins trailing by seven, the knee buckled the wrong way when Griffin tried to field a bad shotgun snap. The Seahawks recovered the fumble deep in Washington territory, setting up a short field goal that helped put the game out of reach. Griffin was done for the evening.
If Griffin had been pulled earlier, the critical turnover might not have happened. And, of course, his knee probably wouldn't be hurt as badly as it is.
"I thank God for perspective and because of that I appreciate the support from everyone. I also appreciate the criticism," Griffin tweeted.
Coach Mike Shanahan said after the game he essentially left the decision for Griffin to keep playing in Griffin's hands, and Griffin said he would probably have defied his coach if ordered to the bench.
"It's a slippery slope, I guess you can say, because you want to help the team," said receiver Pierre Garcon, who faced similar questions this season while dealing with a painful toe injury. "But you want to help yourself in the long run and your career.
"You want to look out for all sides, but it's hard to really know exactly if you're doing the right thing because if you sit out and the team losses, it's like 'I could probably have helped.' If you go out there and don't help the team, it's like, 'I probably should've sat out.' You've just got to make a decision and live with it."
Shanahan was scheduled to address reporters Monday afternoon, but said after the game that he perhaps should have pulled Griffin sooner.
"It's a very tough decision," Shanahan said Sunday. "You have to go with your gut. You have to go with your gut and I did. I'm not saying my gut is always right, but I've been there before. In different situations, I get to know Robert better as time goes on and I'll know how stubborn he is probably more so as time goes on. He's a competitor and I'll probably second guess myself. ... In the second half, should you have done it earlier? I think you always do that, especially after you don't win."
Shanahan's take is muddled by contradictory details that have emerged from the game in which Griffin originally hurt the knee last month against the Baltimore Ravens.
The coach said at the time he was told by orthopedist James Andrews on the Redskins sideline that Griffin was cleared to return to the game, but Andrews told USA Today over the weekend that he didn't get a chance to examine the knee during the one play Griffin sat out after the initial injury.
Shanahan explained the discrepancy by saying Andrews gave the OK for Griffin to return just by watching the quarterback run without doing an examination. Either way, the various versions of what happened cast more doubt on the protocol the Redskins use to determine whether someone is fit to keep playing.
The play-hurt dilemma is a factor every weekend in the NFL. Redskins left guard Kory Lichtensteiger had to leave Sunday's game in the first quarter because he could no longer play on a sprained left ankle that kept him out of practice all week.
"I went out there," Lichtensteiger said. "But, in hindsight, I probably shouldn't have done it."
Griffin's injury and the playoff loss put a damper on the end of one of the best Redskins seasons in two decades. Washington rallied from a 3-6 start to win the NFC East after four straight last-place finishes. Assuming Griffin's knee will again be fully healthy, the future looks brighter than at any time since the Super Bowl era under coach Joe Gibbs in the 1980s and early 1990s.
"I think people have really learned around here if you're down by seven, people aren't packing it in," said safety Reed Doughty, wrapping up his seventh season in Washington. "People aren't getting that 'Oh, the way things used to be' kind of feeling."
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