Bergesen is 1-2 with a 5.13 ERA in eight games, including six starts, at Triple-A Norfolk. He's allowed 45 hits, walked 13 and struck out 17 in 33 1/3 innings.
Bergesen tossed five scoreless innings in Thursday's start after rejoining the Tides' rotation.
Bergesen, who lost his arbitration hearing this winter and is making $800,000 instead of the $1.2 million he sought, is 17-24 with a 4.68 ERA in 83 major league games.
Also, outfielder Xavier Avery will have his contract purchased from Norfolk and report to Camden Yards in time for tomorrow's game. No move will be announced tonight.
Multiple sources have confirmed that Avery will join the team after his agency tweeted it.
Avery, taken in the second round of the 2008 First-Year Player Draft, is batting .273/.373/.469 with six doubles, two triples, five homers and 16 RBIs in 33 games with Norfolk. He's 8-for-8 in stolen base attempts.
The addition of Avery will give the Orioles a four-man bench, so a pitcher will come off the 25-man roster. The Orioles also must clear another spot on the 40-man.