Second baseman Brian Roberts will be in uniform when the Orioles take the field for their first full-squad workout Friday at the Ed Smith Stadium complex, but it remains to be seen how much he will be able to participate in the early drills.

Manager Buck Showalter met with him on the field after Thursday's final pitcher-catcher workout and said the progress that Roberts has made in his recovery from two concussions has been "very encouraging."

"We'll see what tomorrow brings," Showalter said. "I think I've got a pretty good idea after talking to Brian about the way things are going to go, but we'll see what happens. ... He's gone through a lot. It's been a tough road for him."

It also has been a difficult situation for the team, which would benefit greatly if Roberts could make a comeback but cannot afford to assume he'll be available for all or part of the season.

"We all know what it would mean to get him back," Showalter said. "But what are you going to do if he's not able to? It's prudent on our part to prepare both ways, and we have. It's a lot easier to write a lineup, but for every one I've written with him, there's three or four I've written without him."

Showalter had a message for anyone who has questioned Roberts' desire to resume his career as one of baseball's most productive leadoff hitters.

"He played 150 games a year for an extended period of time," Showalter said. "Nobody loves the game of baseball more than Brian Roberts. Nobody probably loves the Orioles more than Brian. I think sometimes we really underestimate his level of frustration with this. I do know he's made some progress that's very encouraging, but I don't think anybody's got a definitive timeline on it."