Roberson, a fleet-footed defensive outfielder, is a .278 career hitter in the Minors. He's logged two brief big league auditions in Philadelphia but spent most of last year at Triple-A Ottawa, where he batted .266 with four home runs and 19 stolen bases. Roberson has stolen 176 bases in seven Minor League seasons, but he's been caught 70 times.
The 28-year-old was named the Eastern League Rookie of the Year in 2005 after batting .311 with 15 home runs for Double-A Reading, and he followed that up by hitting .292 with 25 stolen bases for Triple-A Scranton/Wilkes-Barre in 2006. Roberson, a former ninth-round Draft pick, methodically worked his way through the Phillies organization.
Philadelphia gave him the Paul Owens Award in 2005, honoring him as the organization's Minor League player of the year. Roberson has struck out (486) more than twice as many times as he's walked (224) in his Minor League apprenticeship and has scored more than 70 runs just once in seven full seasons.
Baltimore's incumbent center fielder, Corey Patterson, has filed for free agency and isn't expected to return to the fold. That leaves Payton, who batted .256 as the starter in left field last season, and Redman, who began the year playing Independent League ball and finished it by hitting .318 in 40 games with the Orioles.
The Orioles made room on the 40-man roster by designating outfielder Jeff Fiorentino for assignment. Fiorentino, a former third-round Draft pick, batted .282 with 15 home runs and 65 RBIs at Double-A Bowie last season.
Spencer Fordin is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.