All call-ups should initially come from Norfolk with Double-A Bowie battling for a spot in the Eastern League playoffs. Xavier Avery and L.J. Hoes, two of the organization's top prospects, are unlikely to get the call after their season ends Sept. 5.

Showalter hasn't decided whether he will move right-hander Jim Johnson from the bullpen to the rotation. He said he wants to get through Thursday's call-ups before deciding about Johnson.

The manager hopes to give Johnson some starts in September if the organization decides to move him to the rotation next spring. "I'd prefer that, in a perfect world," he said, adding that even if Johnson doesn't start a game this season, he could still join the rotation in 2012.

Praise for Wieters' durability

Matt Wieters entered Monday's game with a .265 batting average, fifth in the major leagues among qualifying catchers. But Showalter is more impressed with where the young All-Star ranks among the league leaders at his position in another category: games played.

Wieters, who started against the New York Yankees and appeared in his 115th game, ranks fifth among major league catchers in games played. The 25-year-old played in 130 games last year, and Showalter said he is "proud" of Wieters for increasing his workload in his third season.

The key, according to Showalter, is that the 6-foot-5, 225-pound catcher has kept his weight up.

"Matt's done a good job of maintaining his weight this year. Last year, it dipped down pretty good," Showalter said. "I've love to have that problem. … Me, I can't look at a Popsicle."

Around the horn

Machado said he texted Yankees third baseman Alex Rodriguez, who like Machado was a high school phenom from Miami, to let him know he was at Camden Yards and was hoping to meet up. But Rodriguez traveled back to New York to have an MRI on his left thumb. … Jeremy Guthrie, Jo-Jo Reyes and Tommy Hunter will start for the Orioles in this week's series against the Toronto Blue Jays. … Berken, who is on the 15-day disabled list with a right forearm strain, is expected to travel to the Orioles' minor league complex in Sarasota, Fla., this week to begin throwing. First, his wife will have labor induced early Tuesday morning. … Reliever Troy Patton, who attended a court hearing in Texas related to his January arrest on DWI charges, won't be activated from the restricted list until Tuesday. He missed Monday's game because of a flight issue. … Chris Davis will start swinging a bat Tuesday. … Actor Chazz Palminteri threw out the ceremonial first pitch.