The Angels placed Zeferjahn on the 15-day injured list Saturday due to right knee tendinitis.
Zeferjahn recorded two outs in Friday's loss to the Athletics but allowed one run on one hit and two walks with one strikeout. With Zeferjahn off to the injured list, the Angels recalled Chase Silseth from Triple-A Salt Late. Zeferjahn owns a 4.77 ERA, 1.45 WHIP and 72:33 K:BB across 54.2 innings this season.