Vladimir Tarasenko and Robert Thomas scored, Ryan O'Reilly had two assists and Jordan Binnington made 27 saves for the Blues, who had been 4-0 on the road in the Stanley Cup Playoffs.
"They played better than us when you look at the whole game. We had some good things at times, but our consistency wasn't there," O'Reilly said. "We didn't find our offensive structure until later on and it was too late. That happens, (there are) adjustments we have to make. We're disappointed. That wasn't the kind of game we wanted, but it's a best out of three now and we're confident we'll turn it around."
Stars coach Jim Montgomery, who frequently changed lines during the regular season, broke up his top line of Seguin-Benn-Radulov for the game. Seguin played on a line with Jason Dickinson and Zuccarello, and Roope Hintz joined the line with Benn and Radulov.
"What I think it comes down to is guys personally elevating their game," Dickinson said. "If it took shaking up the lines to get guys to do that, then it's a great move by the coach."
Tarasenko gave St. Louis a 1-0 lead at 5:02 of the first period with a wrist shot from the top of the right circle that went under Bishop's arm on the power play. Vince Dunn, who replaced Alex Pietrangelo on the first power-play unit, had the primary assist.
Dickinson tied it 1-1 at 11:23. After Zuccarello's shot from the high slot went wide, Seguin got the puck off the end boards and shot it back on net, where Dickinson got the rebound and scored with a backhand while falling across the crease.
