BALTIMORE -- Rehabbing Orioles closer Mike Gonzalez is scheduled to throw an inning of batting practice at the team's Spring Training facility in Sarasota, Fla., on Monday, marking the first time he will face live hitters since going on the 15-day disabled list.

On Saturday, Gonzalez threw off the mound for the first time and, assuming he comes out of Monday's session OK, he will throw an inning in an extended spring camp game on Thursday.

Gonzalez has been working his way back from a left-shoulder strain that he has said previously started to plague him in the days leading up to April 10, which was his final appearance before being placed on the DL April 15.

Orioles manager Dave Trembley said that there are no plans for Gonzalez beyond Thursday. But given Gonzalez's progression, early June would be a likely target date so long as he experiences no setbacks.

A lefty with a herky-jerky delivery, Gonzalez appeared in three games for the Orioles, pitching to an 0-2 record and an 18.00 ERA, before being put on the shelf. In his absence, the Orioles have relied heavily on Alfredo Simon, who has become the team's de facto closer. A power pitcher, Simon was charged with his first loss and blown save of the season in Saturday's 8-2 loss, surrendering four runs on three hits and recording just one out in the ninth inning.

Trembley said Simon was available if needed on Sunday and chose to not speculate further down the road.

"I believe that's the proper way to go about it," he said. "I can't guarantee that he will close for the next 10 times in a row."

Roberts works his way closer to June return

BALTIMORE -- Orioles second baseman Brian Roberts continued to slowly work his way into baseball-related activities on Sunday and is expected to fly to the team's complex in Sarasota, Fla., sometime this week to progress in extended spring camp.

Roberts took swings off a batting tee and played catch with infield coach Juan Samuel for the second consecutive day prior to Sunday's game against the Indians, and manager Dave Trembley said the initial plan is for Roberts to head south on Wednesday.

Roberts played catch on Friday, but Saturday marked his first full day of activities, with Roberts fielding grounders for the first time since being placed on the 15-day disabled list.

The Orioles' leadoff hitter suffered a herniated disk in his lower back during offseason workouts in Arizona. Following 19 spring at-bats, Roberts was deemed ready to play, but reinjured himself on a slide into second base in the April 9 home opener. He was officially placed on the DL on April 12, retroactive to the date of the injury.

To clear a roster spot for Wednesday's addition of Corey Patterson, the Orioles moved Roberts to the 60-day DL, which would make him eligible to return as early as June 10. Prior to Friday's game, Roberts confirmed that his target date is the first day he's eligible off the DL.

Orioles recall reliever Castillo

BALTIMORE -- The Orioles recalled reliever Alberto Castillo from Triple-A Norfolk prior to Sunday's game, filling the spot vacated by first baseman Rhyne Hughes, who was optioned back following Saturday's 8-2 loss.

Castillo said he got the call following the Tides' Saturday night game in Buffalo, N.Y., and was excited to be back for his second stint with the big league club.

"I like where I am at, pitching-wise," Castillo said. "I'm very happy with where I'm at."

Unfortunately, that didn't translate in his first outing. In uniform and ready to go for Sunday's rubber match against Cleveland, Castillo entered the game in place of reliever Matt Albers. He recorded the last out of the eighth inning, gettting Shin-Soo Choo to hit into a double play, but surrendered a two-run homer to Russell Branyan in the ninth to give the Indians a commanding five-run lead. The Orioles went on to lose, 5-1.

Manager Dave Trembley said the decision to bring up Castillo was part of a lefty-for-lefty swap given that long reliever Mark Hendrickson made Sunday's spot start in place of the injured David Hernandez. The addition of Castillo gives the Orioles bullpen depth and adds another southpaw to go with Will Ohman.

Castillo was 1-0 with a 5.40 ERA in six games for Baltimore before being optioned May 6 to make room for Koji Uehara. After returning to Norfolk, Castillo tossed three scoreless outings, spanning 3 1/3 innings.