CHICAGO (AP) -- Fans at Wrigley Field let out loud boos when the BP Crosstown Cup was presented before the Cubs' game against the White Sox.
BP, which is under fire for its handling of the oil spill in the Gulf of Mexico, is in its first year as title sponsor of the annual six-game series between the crosstown rivals.
The Cubs and White Sox opened a weekend set at Wrigley Field on Friday, with another three-game set at U.S. Cellular Field scheduled for June 25-27.
The cup goes to the series winner or the team that takes the final game if they split the six games.
Both teams have said they would stick with BP, although some of the promotions were scaled back.
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