- The Boston Red Sox placed first baseman Mike Napoli on the 15-day DL, retroactive to May 24, with a finger sprain, the team announced. Right-hander Brandon Workman was recalled from Triple-A Pawtucket, and he allowed three runs in five innings in his first start of the season on Sunday.
- The Philadelphia Phillies placed third baseman Cody Asche on the 15-day DL, retroactive to May 23, with a left hamstring strain, per a team announcement. The team recalled right-hander Justin De Fratus from Triple-A Lehigh Valley.
- The Washington Nationals activated first baseman Adam LaRoche from the 15-day DL and optioned Zach Walters to Triple-A Syracuse, according to a team announcement.
- The Baltimore Orioles recalled Preston Guilmet from Triple-A Norfolk and activated catcher Nick Hundley after placing first baseman Chris Davis on the paternity list. (Via Baltimore Sun's Eduardo Encina)
- The Los Angeles Angels purchased the contract of Wade LaBlanc from Triple-A Salt Lake and optioned Matt Shoemaker to Triple-A, according to a team announcement.
- The Kansas City Royals recalled right-hander Michael Mariot from Triple-A Omaha and optioned Francisco Pena down to Triple-A, the team announced.
- The Milwaukee Brewers sent Jeff Bianchi outright to Triple-A Nashville and recalled Jimmy Nelson from Double-A Huntsville, per a team announcement.
- The New York Mets recalled right-hander Vic Black from Triple-A Las Vegas, according to a team announcement. Matt den Dekker is on his way to New York, though no official move has been made.
- The Arizona Diamondbacks recalled Zeke Spruill from Triple-A Reno to make the start as the 26th man in the team's second game of a doubleheader, per a team announcement. The right-hander allowed three runs on 10 hits in 5.1 innings.
- The San Diego Padres designated right-hander Blaine Boyer and Billy Buckner for assignment and recalled Tommy Medica from Triple-A El Paso, the team announced.
- The Baltimore Orioles optioned Steven Lombardozzi to Triple-A Norfolk, via the Baltimore Sun's Eduardo Encina.
- The Chicago White Sox designated right-hander Frank Francisco for assignment, and he elected free agency, according to a team announcement.
- The Angels are hoping that outfielder Josh Hamilton will be able to join the team during its series in Seattle starting Monday, or against the A's in Los Angeles in the ensuing series, according to the Los Angeles Times' Bill Shaikin. Hamilton last played on April 8, when he tore ligaments in his thumb.
- The Chicago Cubs singed free agent outfielder Manny Ramirez to a minor league contract, per a team announcement. General manager Theo Epstein noted that he sees Ramirez as a player-mentor, making it clear that the former All-Star would not spend time with the big league club.
- Rehab Assignments: Mat Latos (Louisville), Travis d'Arnaud (Binghamton)