"We were okay in the first period, but we were terrible in the second period," Red Wings coach Jeff Blashill said. We started the second period with a power play and a chance to make it 3-1. Instead, we gave away the momentum."
The Red Wings had a 2-on-0 shorthanded breakaway at 16:55, but Nilsson stopped Frans Nielsen's shot. Nielsen doesn't have a point in 19 games this season.
"I was just glad I could get my pad down and he didn't lift the puck," Nilsson said. "Making a save like that is huge for my confidence, but it is even more important to go into the third period with that two-goal lead."
Detroit outshot Ottawa 16-3 in the third period but didn't score until Anthony Mantha cut it to 4-3 at 17:14 with Bernier on the bench for an extra skater.
"If we played three periods like that I'd like our chances, but we need to get a much better net-front presence," Blashill said.
Duclair gave the Senators a 1-0 lead at 3:08 of the first period, knocking down Thomas Chabot's pass with his glove and breaking in to score his eighth goal of the season.