Lars Eller also scored for the Senators (38-24-9), who have won four straight, including a 2-1 victory at the New York Rangers on Monday, and are 15-3-2 in 20 games since Jan. 25. Linus Ullmark made 32 saves.
Ottawa moved into the second wild card into the Stanley Cup Playoffs from the Eastern Conference. The Senators are one point ahead of the Red Wings and tied in points with the New York Islanders, who have played one more game and lost 4-3 to the Chicago Blackhawks on Tuesday.
“This was a gutsy, gutsy game,” Senators coach Travis Green said. “We came in after playing last night to face a rested team and found a way to win.”
Multiple injuries to Ottawa defensemen, including Thomas Chabot (upper body) and Lassi Thomson (undisclosed) on Monday, paved the way for Yakemchuk and Jorian Donovan, a fifth-round pick (No. 136) in the 2022 NHL Draft, to each make his NHL debut against Detroit.
“I’m proud of both of them,” Green said. “We got a big game from (Yakemchuk). He’s a special player, and I thought (Donovan) did what we needed him to do.”
Dylan Larkin scored in his return from a lower-body injury, and Dominik Shine also scored for the Red Wings (38-25-8), who have lost five of their past seven games (2-4-1). John Gibson made 18 saves.
“It was good to be back out there with the guys,” said Larkin, who played for the first time since March 6 after missing seven games. “But the room is mad, because this was a big game. We have 11 games left and we have to be better than this.”
The Red Wings appeared to take a 1-0 lead on Alex DeBrincat’s power-play goal at 15:35 of the first period, but the play was overturned after the Senators successfully challenged for offside.
Tkachuk then put the Senators ahead 1-0 with a power-play goal at 17:15. As Gibson got into position to stop Tim Stutzle’s shot, Tkachuk tipped it past his blocker. Yakemchuk picked up the secondary assist for the first point of his NHL career.
“This isn’t a normal first NHL game, it is more like a first game in the playoffs,” Tkachuk said. “Yakemchuk and (Donovan) were both amazing.”