A's activate Ryan Cook

The Oakland Athletics activated relief pitcher Ryan Cook, who'd been sidelined with shoulder tendinitis, off the disabled list Monday.

Cook has a 2.30 ERA over the past two seasons and has struck out more than a batter per inning -- including 67 strikeouts over 67 1/3 innings last season -- and has filled in at closer at times, compiling 16 career saves.

Reigning AL saves leader Jim Johnson, signed by Oakland during the offseason to replace Grant Balfour, had lost back-to-back outings before earning his first with the A's on Sunday.

The Associated Press contributed to this report.