BALTIMORE -- Major League Baseball has announced the 30 winners of the 2013 Honorary Bat Girl Contest, which recognizes baseball fans who have been affected by breast cancer and have a commitment to getting rid of the disease.

Krista McKenzie McElwain will be honored by the Orioles.

There's one winner per team, and they'll be recognized on the field at ballparks on Sunday, which is Mother's Day, or an alternate date for teams who will be on the road on Sunday.

For more information, including a complete list of the winners and all of their stories, go to www.honorarybatgirl.com.

Roberts slated for Thursday surgery on hamstring

BAL@TB: Roberts appears to injure leg while sliding

BALTIMORE -- Orioles second baseman Brian Roberts will undergo right hamstring surgery on Thursday in Dallas and is expected to be out about six more weeks, further delaying his comeback hopes this season.

Roberts is scheduled to be operated on by Dr. Daniel Cooper at the Carrell Clinic. Baltimore said the recovery time is expected to be about six weeks, and Roberts will report to Sarasota, Fla., afterwards.

"He's determined. He's determined to get it right and get back," manager Buck Showalter said following Wednesday's 5-3 win over the Royals. "He's very frustrated by it, but he's determined. He's had to fight back from a lot of things. A lot of guys would have pulled the dirt in, but he's not going to do it. He thinks we've got a chance to be competitive this year and he wants to be a part of it, because he thinks he can help us, and so do I."

The surgical procedure is called a semitendinosus release, involving one of the three muscles that make up the hamstring itself.

Roberts sustained the injury while sliding during a game against the Tampa Bay Rays on April 4, and he needed to be helped off the field. The Orioles placed him on the 15-day disabled list.

Injuries have plagued the former All-Star the last few years. Roberts has played in just 118 games since the start of the 2010 season.

Markakis gets breather as designated hitter

BAL@LAA: Markakis ropes an RBI double down the line

BALTIMORE -- Nick Markakis was in the Orioles lineup as usual for Wednesday's game with the Royals, but as the designated hitter and not the starting right fielder.

Markakis made his third start as the DH, with Chris Dickerson taking over in right field and batting ninth. For Markakis, it's a bit of a break, but something he adjusts to when it happens.

"It's different. You've just got to stay loose, stay stretched," Markakis said. "It's good -- it gives me time off, gives me a chance to get my feet back under me. It's a different mindset, but it's good every once in a while."

Markakis said manager Buck Showalter had told him earlier this season that he'd be the DH at times just for that reason -- getting a little break.

Showalter is going to rotate players in the DH spot from time to time to give various people a break, something often needed over a 162-game season.

"It's tough to go out there and play every day, especially for a long time over years," Markakis said. "Like I said, it's good for you every once in a while just to get your feet back under you, and kind of get your head on straight."

Markakis is off to a good start so far in 2013. The veteran right fielder entered Wednesday with a .270 average, three homers and 15 RBIs.

Gonzalez pushed back in rotation with blister

BAL@NYY: Gonzalez induces a double play to escape

BALTIMORE -- The Orioles will start right-hander Freddy Garcia in Thursday's series finale against the Royals.

Miguel Gonzalez was the scheduled starter for Thursday, but the Orioles pushed him back due to the blister on the side of his right thumb. He pitched six innings on Friday in a loss to the Angels, and the blister forced him from the contest.

Gonzalez will have a work day on Thursday, throwing with a band-aid on, something Major League rules prohibit a pitcher from doing during a game.

"As long as this heals 100 percent, that's where I want to be, and I'll be able to throw with it," Gonzalez said. "It's tough, that's where you hold the ball."

Manager Buck Showalter said the O's are hoping to start Gonzalez on Saturday. But if the right-hander can't go, they'll either make a move to bring someone in or give the ball to a pitcher on the current roster.

"We've taken some provisions in case we don't think Saturday is a good idea or not," Showalter said. "Saturday is as far back as we can push him."

There is still a possibility that Gonzalez could land on the disabled list. But Showalter said the Orioles will just wait and see how Gonzalez does after throwing on Thursday and make a decision from there.

Worth noting

• Orioles closer Jim Johnson recorded his 13th save on Wednesday to match Randy Myers (1997) for the franchise record of 34 straight saves. Johnson's streak started on July 30, 2012, and is the longest-running saves streak in the Majors.

• Brian Matusz had stranded each of the 26 runners he inherited coming out of the bullpen this year until Alex Gordon's two-run homer on Tuesday night. Matusz came in after a 48-minute rain delay with one runner on, and Gordon homered later in the inning.

• Defense continues to be a big plus for the Orioles this season. Heading into Wednesday's game, Baltimore was tied for the third fewest errors in the Major Leagues. The O's had made only four miscues in their previous 18 games.