Sometimes he got too comfortable.
"He's had some tremendous games this year," Ducks coach Joel Quenneville said. "He has some tremendous moments where I'm sitting there, saying, 'You can't do that in this league. You can't try that at that time of the game. You can't do that against that type of defenseman or make that play where you're trapping everybody.'"
The Ducks have tried to find a balance, letting him flash his talent to an extent, reining him in when necessary.
"When we're showing clips to the guys, whether it's individually or with the team, sometimes he's in it," Quenneville said. "I think he understands and he absorbs it, and he doesn't feel bad. He just knows it's part of the learning curve, and we try to do things in a positive way with him and all our guys, but he probably gets talked to more than most guys."
Quenneville smirked and paused.
"Or everybody," he continued with a big laugh.
Quenneville called him "very likeable."
"You enjoy trying to help him, and I think he understands when your tone gets a little more direct, but he's a sharp kid," he said. "I mean, he understands how he's got to get better. He's willing to do whatever it takes."
Sennecke helped the Ducks make the playoffs for the first time since 2018 and then earn their first series win since 2017 when they defeated the Edmonton Oilers in six games in the first round. He scored a goal in a 7-4 victory in Game 3 of that series.
"He was great," Killorn said. "Maybe he didn't produce as much as he wanted to, but in terms of chances created and what he brings to our team, even on the power play, he made a huge impact in the games."
Sennecke is still learning about the playoffs.
He said you expect the pace to be quicker, but you don't know how fast it is until you experience it firsthand. Quenneville said he needs to be stronger in puck battles, as most young players need to be when they're maturing physically. Despite his goal in Game 2 against Vegas, he played only 11:03, the least he has in the playoffs to this point.
This is just the start for him.
"He's not afraid of the physicality of the game at all and he's really good at protecting pucks, and he's super young, so that's only going to get better," Killorn said. "As he gets older and stronger, he's going to be hard to play against."