Hart was to be the backup to Brian Elliott, who will start Saturday for the first time since sustaining a lower-body injury Nov. 15. But the rookie goalie will not dress and be out at least 10 days because of a lower-body injury.
Hart was pulled in the first period of his past two starts. He allowed three goals on nine shots in a 5-2 loss to the Tampa Bay Lightning on Tuesday, and three goals on nine shots in a 5-1 loss to the Montreal Canadiens on Thursday.
He was replaced each game by Elliott; the two relief appearances were his first games since returning from a conditioning stint with Lehigh Valley in the American Hockey League on Tuesday.
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Hart said Friday that as much as he wanted to start against the Penguins, he's taking a bigger-picture approach.
"Even though it's an outdoor game, it's a crucial two points for us," Hart said before the injury was announced Saturday. "The last two games I haven't been at my best and Brian's done a good job coming in in relief both times. It is what it is, you can't control that.
"What you can control is how you respond to it. It's disappointing but you've got to approach it the right way and can't let it set you back. You've just got to come back ready to work. We've got a lot of hockey coming up and that's where the focus is at."
The Flyers (28-26-7) are eight points behind the Penguins for the second wild card into the playoffs from the Eastern Conference.
Hart is a big reason they've gotten that close. Prior to the past two games, he was 13-6-1 with a 2.53 goals-against average and a .924 save percentage in 20 games since making his NHL debut Dec. 18. The Flyers, who were last in the Eastern Conference when Hart made his debut, have gone 16-11-3 since.
"I said to Carter that this right now, this is going to hurt that you are not going to play," Flyers coach Scott Gordon said before the injury was announced. "I know you are going to play a lot of games in the NHL and you're probably going to have a few of these outdoor games. But the biggest thing is, this is our biggest game of the year, and as far as a lineup decision, what's best for the team. ... In my heart it's easy to choose Carter. But from a standpoint of what's right for the team, I thought this was the right decision.
"If we base it on performance from a week ago or last Sunday, we are probably talking about Carter. But right now, given the way it's gone I just felt like I wanted to give our team the best chance for Saturday to win. ... You're not getting demoted here, you're not being pushed aside. You've earned the right to be here, played excellent. We all believe in you, the team believes in you."