What he also saw was a team that continued to grind through injuries to key contributors. Forward Nikita Kucherov left after slamming into the post, goaltender Ben Bishop gutted through another start and Tyler Johnson stayed in the lineup and played almost 18 minutes.
The Lightning are down 3-2 going into Game 6 against the Chicago Blackhawks, but don't tell them they're out.
"I can never sit here and say our guys are not gaming it out," Cooper said Sunday. "Sure, we've had injuries. I'm sure they've had injuries. But our will's been unreal.
"Somehow we're going to have to find a way to scratch a little bit more out. No doubt they will."
On the injury front, Kucherov travelled with the team, and Cooper deemed him "in considerably better shape" than he was Saturday night when he went shoulder first into the post. Cooper wondered if Kucherov would return, but the Lightning's second-leading scorer, is no safe bet one way or the other for Game 6 Monday night.
Bishop, according to Cooper, was feeling much better after his return to the net. It didn't sound like Bishop was in any danger of missing another start.
While the Blackhawks have been remarkably healthy, the Lightning, especially lately, have had to battle through.
"I don't think any team is 100 per cent," defenceman Jason Garrison said. "I think it's just guys are obviously competitors, willing to pay the price. They don't want to take themselves out of the lineup."
Injuries not withstanding, the Lightning have faced elimination on the road twice before in the playoffs and beat the Detroit Red Wings and New York Rangers. Inexperienced two months ago, Tampa Bay now has plenty to draw from going into its toughest challenge yet.
"Each series in this playoffs so far, we've been challenged," defenceman Anton Stralman said. "We had to go into New York with the odds against us. Not a lot of people thought we could pull that off. I think there's a strong belief in our team, within the group we have."
There's also more recent memories to consider. Cooper said his players were disappointed with "a little rage" mixed in after losing 2-1 to Chicago at home Saturday night.
If the Lightning's coach could bottle that for this elimination game, he would.
"Our group was the angry group," Cooper said. "If they're going to be angry birds tomorrow night, that's that I want. Usually they're rock solid when they come out with that mentality."
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