"I thought we skated really well, and we had a lot of chances, but we didn't put them away," said Torey Krug, who scored Boston's goal. "We didn't take advantage on our power play (0-for-4) and they got a goal on theirs, and that was the difference."
Andreas Athanasiou scored two goals and Jonathan Bernier made 39 saves for the Red Wings (14-39-4), who won for the second time in 12 games (2-9-1). They had been shut out in three of their previous four games.
WATCH: [All Bruins vs. Red Wings highlights]
"This is obviously a good test for us," Athanasiou said. "This shows everyone in the room that if we compete, we can beat anyone."
Despite playing for the worst team in the NHL, Bernier is 7-5-0 with a 1.97 goals-against average and .940 save percentage in 13 games since Dec. 12.
"When you have a goalie playing like that, he does two things for the team," Red Wings coach Jeff Blashill said. "First, he gives you a lot of confidence, but the big thing is he keeps you in a lot of games without losing your momentum."
The Bruins (34-11-12) were 10-2-1 in their previous 13 games but lost in Detroit for the second time this season.
"It's a tough loss for sure, it felt like the puck was right around the net a lot, but we were never in the right spot," David Pastrnak said. "We needed the power play to be better."