Ruh roh.

If the Boston Bruins force Game 7 in the Stanley Cup finals, that — and stronger expressions — is going to echo across St. Louis after the city’s newspaper prematurely published congratulatory messages and images about the Blues winning their first NHL championship. Only subscribers could see the mistake in the St. Louis Post-Dispatch’s E-edition, ESPN reported, and it was removed.

Game 6 is Sunday night in St. Louis. The Blues hold a 3-2 series lead.

Images of the mistake, captured by a Twitter user, included the obligatory congrats from Enterprise, with a “special cupholder” yuk from the auto-leasing company and namesake of the team’s arena. There was also an image that read “Congratulations to our Champions” and a heartfelt letter from Tom Stillman, the team’s chairman and governor.

“All of us will remember where we were, what we did and how we felt when the Blues brought the Cup home,” the note said.

It didn’t take long for the Post-Dispatch to offer an explanation and apology.

“In preparation for the outcome of the Stanley Cup finals, some of our readers got a sneak peek at what our advertisers are hoping to say to the Blues, the fans and St. Louis,” the Post-Dispatch tweeted to users who noticed the gaffe. “We apologize for the sneak peek and hope to share their messages with everyone very soon!”

Hey, it can happen to journalists who routinely prepare content, just as companies have championship apparel suitable to sell for each team. One user, a self-described Vancouver Canucks season ticket holder, offered a warning.

“You know STL will lose now right?” he tweeted. “The Bruins will pull a 2011 and use this as motivation, just as they did when they heard about the Canucks planning the parade... sincerely a Canucks fan”

Think the Bruins are going to hear about the gaffe?

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