Office Costars John Krasinski and Jenna Fischer Continue to Trade Stanley Cup Trash Talk

The battle for the Stanley Cup between the St. Louis Blues and the Boston Bruins is tearing apart former Office costars John Krasinski and Jenna Fischer.

As the two teams head into game 7 of the NHL’s annual tournament on Wednesday — in a final tie-breaker game that will determine who takes home hockey’s top prize — Krasinski and Fischer, who played husband and wife Jim and Pam in the beloved NBC comedy series, have been talking trash online.

It all began back in May, when it was determined the Blues and the Bruins would be in the Stanley Cup Finals together.

Fischer, 45, hails from St. Louis, so the Blues are her hometown NHL team. Meanwhile, Krasinski, 39, is a Boston boy, and known fan of the Bruins.

With their competitive teams, the two actors and sports fans developed a healthy rivalry between themselves.

“This feud has been going on for a long time between us,” Fischer explained to NBC News on Sunday night. “When we were shooting the show, the Red Socks and the Cardinals were in the World Series. And [costar Phyllis Smith] and I — Phyllis is from St. Louis — we would be in my trailer cheering for the Cardinals, and he had [costars B.J. Novak and Steve Carrell] in his trailer cheering for the Red Sox. And they swept us in 4.”

“It is my turn. It is my turn to rub it in his face,” Fischer said. “So let’s go Blues!”

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That may be the case, but Krasinski — and the Bruins — aren’t giving up just yet.

Ahead of Sunday’s game 6 and with the Blues ahead, Fischer was feeling confident. “Uh oh.@johnkrasinski Looks like Pam might be going home with Stanley,” she tweeted. “Who would have guessed! #StanleyCup #LetsGoBlues“

“Wow… this is how you wanna play this Fischer?…” Krasinski tweeted back. “Ok. Game ON! #BruinsIn7 #StanleyCup.”

But with the Bruins’ 5-1 win, Fischer was put back behind, and Krasinski on even playing field.

“Soooooo… I should invite someone else to game 7?” Krasinski teased Fischer.

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Wednesday’s game 7, in Boston, will determine a final winner in the Blues and Bruins situation.

But no matter what happens, Fischer and Krasinski’s friendship will likely survive.

During an appearance on Watch What Happens Live with Andy Cohen in 2016, Fischer said that Krasinski was “like my partner” during their time together on The Office, which ran for nine seasons from 2005 to 2013.

“We will always be close because of it,” Fischer said.