The Hollywood heartthrob was eating lunch at Eric's Gourmet, said Sheri Oscarson, an employee at Peak Performance Chiropractic, whose office is across from the eatery.
When asked for a picture, Mr. Pitt politely refused, said Ms. Oscarson.
Staff at Eric's Gourmet confirmed that Mr. Pitt was there, but they didn't know why.
The film, which is being shot in Oakland, is based on a book of the same title that focuses on Mr. Beane's innovative strategy for winning games without big-budget players. Due for release in 2011, the movie will also star big league actors Philip Seymour Hoffman and Jonah Hill.