Mattheus had a 2.84 earned-run average with one save in 11 appearances for Salt Lake City. Angels closer Huston Street and setup man Joe Smith have pitched in the last three games.
"We have a bullpen we're trying to keep together," Angels Manager Mike Scioscia said. A lot of these guys have pitched a lot. Mattheus gives us a little more depth there."
Cam Bedrosian, who has a 2.19 ERA in seven games for Salt Lake City, pitched two innings Thursday, as Scioscia opted for Mattheus.