The long-rumored announcement was reported as a done deal by MLB.com analyst Jim Duquette and confirmed by a baseball source to MLB.com. The news ends a lengthy negotiation process in which Peterson was interviewed several times over a month-and-a-half period before the one-year deal was reached.
Dan Duquette, Baltimore's executive vice president of baseball operations, was optimistic throughout the process, saying last week that he felt the two sides would be able to reach a deal. The patience and persistence paid off, netting the Orioles a highly respected pitching guru who is known for implementing techniques that focus on reducing injury risk.
A former pitching coach with the Athletics, Mets and most recently the Brewers, Peterson was let go after the 2010 season when Milwaukee made a managerial change.
Peterson takes the place of Alan Dunn -- who left the organization in June 2011 to accept the job as pitching coach for Louisiana State University -- although the exact details of his new title and additional responsibilities are still a work in progress.
Brittany Ghiroli is a reporter for MLB.com. Read her blog, Britt's Bird Watch, and follow her on Twitter @britt_ghiroli. This story was not subject to the approval of Major League Baseball or its clubs.