Toronto police are urging Blue Jays fans to keep their emotions in check after an unruly crowd tossed beer cans onto the field during the team's suspenseful series-winning game, leading to at least one arrest.

But police say Wednesday's flare-up is "not indicative" of typical fan behaviour and they don't expect a repeat of the incident that left a man facing a mischief charge.

Albert Grummitt was arrested after a baby was hit by the spray from a thrown beer can. He has since been released and is due in court on Nov. 24.

Police Insp. Chris Boddy says officers will be keeping an eye on fans as they pack into bars and other venues to watch the Jays take on the Royals in Kansas City on Friday in the first American League Championship Series game.

And they'll be monitoring the crowd when the Jays play at home for Game 3 on Monday.

The force has been preaching restraint on social media using the hashtag #FanEtiquette as Jays mania reaches a fever pitch.

"The actions you take will not affect the outcome of the game, only effect the perception of .Toronto. Keep classy Toronto #FanEtiquette," Const. Wendy Drummond tweeted during Wednesday's high-stakes game.

"Our fans got their feathers ruffled, but hopefully they regain their composure #FanEtiquette," she said in another tweet.

As tensions peaked Wednesday, the players themselves were among those urging fans to settle down.

"It's unfortunate that it had to come to that," Boddy said.

"But I don't expect that we're going to have any issues like that again throughout the series -- that was a one-time incident in our opinion -- but we're going to be there just the same making sure everybody's safe."

Fans tossed beer cans and other debris onto the field after a controversial call in the seventh inning that gave the Texas Rangers a short-lived lead. The Jays eventually won the game 6-3 to win their American League Division Series in five games.

Police say the baby was with her mother in the front row of the Rogers Centre when the can was tossed their way.

Television cameras captured a teary woman holding her baby shortly after the incident.

Police said the baby wasn't hit by the can and is OK.