They also have to figure out a way to get the power play clicking again.
The Senators gifted the Penguins opportunities to own the first period, giving them four power play chances, including a 5-on-3 for 45 seconds. But the Penguins didn't score.
Ottawa took a 1-0 lead on Pageau's goal at 14:32 of the first period, after Pittsburgh was already 0-for-3 on the power play.
The Penguins got a fifth power play at 7:33 of the second period, but again couldn't convert. It had 10 shots on goal and 15 total shot attempts on their five power plays.
"The movement wasn't there," Sullivan said. "The passes weren't crisp."
The Penguins are 0-for-10 on the power play in the past three games.
"I think we know we have a lot of capable guys out there," forward Chris Kunitz said. "They'll look over the tape, they'll get ready and they'll be ready for Game 2."
That was the general vibe the Penguins were giving out after Game 1. Nobody expected any panic, not from this group, so it was more of a feeling of, 'OK, we saw it, we understand it, and now we know how best to attack it.'
That might be the confidence, or borderline arrogance, that this team has, that winners typically have. Regardless, the Penguins genuinely don't feel they gave the Senators much in Game 1, especially their best shot.
That better come in Game 2. There is no more room for learning experiences.
"We have to execute," Kunitz said. "We have to be better. We had spurts and shifts that we executed really well in their zone, but we have to put more pucks there. If we're going to spend that much time there, we have to put pucks [on net]."