Miguel Montero singled in two insurance runs in the ninth inning.
Edgar Gonzalez (3-2) -- filling in for Randy Johnson, who went on the disabled list Friday -- allowed two hits and a run over five innings to get the win. Gonzalez had just two days of rest after pitching three innings against the New York Yankees Wednesday.
Melvin Mora homered and drove in three runs for Baltimore, which has lost seven in a row and 12 of its last 14 games.
Daniel Cabrera (5-8) lost for the fifth time in seven starts. He gave up six hits and five runs over eight innings.