It seems the president gave a video message about the 100th anniversary, and a majority of the crowd booed him, with a smattering of cheers mixed in. This is coming from a blue state. At least Michelle only got booed by NASCAR fans. Here a couple of tweets from the game. Gordon Edes is a Red Sox reporter.
Eric Fehrnstrom @EricFehrn
At Red Sox game, President Obama comes on big screen to recognize Fenway's 100th anniversary, followed by loud chorus of boos.
Gordon Edes@GordonEdes
People booing message from President Obama. Mixed with cheers