Mahoney, 25, will take the roster spot vacated by pitcher Chris Tillman, who was optioned to Double-A Bowie following yesterday's 4-2 victory over the Mariners. Mahoney will meet the Orioles in Anaheim.
Mahoney is batting .256 with 14 doubles, five home runs and 38 RBIs in 85 games with the Tides. He's hitting .306 in his last 10 games.
Jamie Hoffman pinch-hit for Mahoney after two at-bats today. The Orioles had made their decision.
It's a simple transaction because Mahoney, listed at 6-foot-6 and 240 pounds, is on the 40-man roster. He most likely will return to the Tides next weekend when the Orioles recall Tillman.
This will be Mahoney's first promotion to the majors. He hadn't played above Double-A before this season.
Mahoney was given the Brooks Robinson Award in 2010 as the organization's top position player in the minors, but he had two stints on the disabled list last year with a torn left quadriceps.
A team official confirmed that Mahoney is being called up. Bowie hitting coach Denny Hocking sent out a tweet late last night congratulating Mahoney, one of his former players, on the promotion.