The ad, featuring a large photo of a boy in Cards gear and another wearing Red Sox apparel, was headlined, "From one great baseball town to another."
The message from there -- signed by Red Sox principal owner John Henry, chairman Tom Werner and president/chief executive officer Larry Lucchino -- reads in full:
"On behalf of our partners and the entire Red Sox organization, thank you St. Louis. The warm Midwestern welcome you extended to our team and our fans during this year's hard-fought World Series is truly appreciated. Your region, its people, and the entire Cardinals organization represent everything that's great about baseball.
"We share the same colors and rich, storied baseball history that stretches from Musial and Williams, to Molina and Pedroia. We're both home to the most loyal, passionate fans in the game. And the four World Series in which we've gone head-to-head are still etched in the memories of those who love our sport.
"So we tip our hats to each and every one of you. We look forward to seeing you again next August. Let's hope that it's just a prelude to meeting again in October."
Cash Kruth is a reporter for MLB.com. Follow him on Twitter at @cashkruth. This story was not subject to the approval of Major League Baseball or its clubs.