Major League Soccer's disciplinary committee issued the ruling for Bernier's "reckless challenge that endangered the safety of Toronto FC forward Ryan Johnson."
Bernier was shown the yellow card after his aggressive challenge left Johnson limping in the 94th minute of TFC's 3-0 victory last week at Montreal.
The Brossard, Que., native will sit out Montreal's match at D.C. United on Saturday night.
Johnson said after the game that Bernier should have got a red card.
"If I got really hurt I would have been more upset," he said. "I'm glad I was able to walk away from that tackle. That was probably one of the worst tackles I've seen."