Guentzel was moved off Crosby's line in the second period of Game 7, when he played a Penguins-low 13:59 in a double-overtime game. That was his lowest ice time of the postseason, until Monday.
Guentzel played 11:52 on the fourth line in Game 1.
"We felt in the last series that he might have been wearing down a little bit," Sullivan said. "The coaching staff was trying to be proactive and trying to find ways to maybe cut his minutes a little bit so that we would get more productive minutes from him. Quite honestly, to take a little bit of pressure off him. But by no means did we lose faith. We know he's a good player. He's a high-quality player."
Sullivan spent time going over Guentzel's game with him in the past week, including trying to coach him up, keep him positive.
"Jake and I have had a few discussions here over the last week about just the coaches' assessment, trying to help him work through some of the challenges, like we do with all of our players," Sullivan said. "He's a real good player. He gets a great goal for us tonight. I think that's an indication of the type of player that he is and his capability. But certainly I think he's a guy that we know we can rely on here to help us win games."
He did it Monday, scoring on what at the time seemed like an improbable shot because it seemed like the Penguins would never get another one with the way they were playing.
In fact, Pierre McGuire noted on NBC's broadcast after the goal that before Guentzel came on the ice to score Sullivan yelled on the bench, "Is somebody on this team going to get a puck on goal?"
Why not the player who hadn't scored in eight straight games? Why not the player who hadn't shot the puck all night? Why not Guentzel?
"For him to come out and get a big goal like that was huge," Crosby said. "It wasn't our best game, but he stepped up and came through for us."