The Los Angeles Angels placed closer Huston Street on the 15-day disabled list because of inflammation in his right knee two days after he blew a three-run lead in the ninth.
Street surrendered five runs, including a three-run homer to Boston's Dustin Pedroia,in a 5-3 loss on Sunday.
The right-handed Street has converted only nine of 12 save opportunities this season.
To take Street's place on the roster, the Angels recalled right-handed reliever Mike Morin from Triple-A Salt Lake City.
Manager Mike Scioscia said that in Street's absence, the Angels are prepared to use a committee of pitchers in the ninth inning.