Montembeault made two breakaway saves 14 seconds apart to keep the game scoreless early in the second period. He made a glove save on Olivier, who had received a pass from Eric Robinson after exiting the penalty box, at 3:24 before stopping a backhand from Gustav Nyquist at 3:38.
"It's huge," Montreal forward Kirby Dach said. "[Montembeault] has been great for us all year every time he's been in the net. He gives us a lot of confidence. He makes great saves all the time, timely saves. That's all you can ask."
Olivier gave Columbus a 1-0 lead at 1:08 of the third period. He intercepted a weak clearing attempt by Mike Matheson and scored short side from the top of the right circle.
Xhekaj responded 90 seconds later at 2:38 to tie it 1-1, shooting through traffic from the left point.
"Every game I just tried to get pucks through," Xhekaj said. "Those floaters have been working good for me, so I've got to just keep it up."