President Barack Obama found out that Boston Red Sox fans didn’t want to hear about the team’s trade of Kevin Youkilis. (Stephan Savoia / AP)

No, there’s no sugarcoating this: Bostonians were booing when President Barack Obama violated the “too soon” rule and thanked them for trading popular infielder Kevin Youkilis to his baseball team of preference, the Chicago White Sox, over the weekend.

“Boston, I just want to say thank you for Youkilis,” Obama said. When folks who’d purchased tickets for a fundraiser at Symphony Hall let him hear about it in the time-honored tradition, Obama was reminded of the perils of mixing politics and sports. “I’m just saying, he’s going to have to change the color of his socks,” Obama said, laughing.

The Red Sox got infielder Brent Lillibridge and pitcher Zach Stewart in return for Youkilis, a fixture on two World Series winners with the Red Sox. In his debut with the White Sox on Monday, Youkilis went 1-for-4 in Chicago’s 4-2 loss to Minnesota. The Symphony Hall crowd didn’t know that at the time.

“I didn’t think I was going to get any boos out of here,” Obama said. “I should not have brought up baseball. I understand. My mistake. You’ve got to know your crowd.”

Know them by the color of their Sox.

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