The Red Wings, coming off victories against Edmonton on Saturday afternoon and at St. Louis on Thursday night, were seconds away from settling for a point after Henrik Zetterberg set up goals for Pavel Datsyuk and Damien Brunner in the first period.
Los Angeles, which got within a goal late in the first period on Anze Kopitar's goal, pulled goaltender Jonathan Quick to add an extra skater. Forward Kyle Clifford got off the bench in time to keep the puck in Detroit's end. Clifford's shot rebounded off Jimmy Howard and Alec Martinez scored on a putback to make it 2-2 at the 19:07 mark of the third period.
With Quick back in, the Kings failed to clear the puck and Ericsson took advantage with a slap shot from above the right circle that trickled in for the win.
Ericsson refused to be hailed for the victory.
"We owe Jimmy this one," Ericsson said.
Howard made 45 saves, his highest total in more than a year.
"Every single night, points are at a premium," he said. "You have to get points to stay in the mix and stay in the playoff hunt."
The Kings have some work to do over their last 38 games to have a chance to defend their championship. They started the day among the Western Conference teams with the fewest points and have won only one of their last five games.
Kopitar, though, was more encouraged than discouraged by the latest loss.
"That was our best game of the year," he said. "Playing like that, you're going to win more times than not."