Erik Karlsson had a goal and two assists for his second straight three-point game, and Stuart Skinner made 20 saves for the Penguins (36-21-16), who have lost three of four and are one point behind the New York Islanders for second in the Metropolitan Division.
Pittsburgh played without forwards Sidney Crosby (lower body) and Evgeni Malkin (upper body), who are each day to day.
“We focus in on what we can control,” Penguins coach Dan Muse said. “I don’t think anybody is going to walk out of today feeling good about our game. We’ve got to be better. It’s all of us, myself included.”
Anthony Mantha put Pittsburgh up 1-0 with a power-play goal at 2:12 of the first period. Karlsson sent a wrist shot on net from the blue line and Mantha tipped the puck through Oettinger's pads from in front.
Justin Hryckowian tied it 1-1 at 2:10 of the second period. Colin Blackwell had a shot blocked by Ben Kindel and it bounced to Hryckowian near the right circle for a wrist shot into an open net.
Karlsson put the Penguins back up just 48 seconds later at 2:58 when he buried a wrist shot from between the circles that went bar down.
“I think it was a winnable game for us today,” Karlsson said. “Ultimately, we didn’t do the work. They’re a good team for a reason. They showed that today.”
The Stars scored three straight goals in a 4:26 span to take the lead.
Robertson evened the game 2-2 at 7:12 while on the power play. He took a pass from Rantanen and put a wrist shot from between the circles past a screened Skinner into the top right corner for his 40th of the season.
“Not forcing it was a big thing,” Robertson said. “And, I mean, having a lot of talent out there helps.”