ANAHEIM, Calif. — The Los Angeles Angels activated setup man Scot Shields from the 15-day disabled list today and optioned right-handed reliever Rich Thompson to Triple-A Salt Lake.

Shields has pitched 361 2/3 innings over the previous four seasons, the most by any reliever in the majors. But his spring training was curtailed by discomfort in his shoulder and tightness in his forearm.

"I was hoping I wouldn't have to spend any time on the DL," Shields said. "But any time you have a problem, it's nothing you want to mess around with. I'm just fortunate to be back this early."

Shields threw 18 pitches on Thursday for Salt Lake in a one-inning appearance that persuaded the Angels to bring him back from his first stint on the DL. He struck out three and allowed two hits, throwing first-pitch strikes to all five batters.

"This is the first time I've ever missed any games ever — college, minor leagues or the big leagues. So it definitely hurt sitting around watching," Shields said.

Shields, was 4-5 with 3.86 ERA in 71 appearances last season. He pitched a career-high 148 1/3 innings in 2003, and has had two seasons with 100 or more strikeouts during his five full seasons with the Angels. His 39 career victories are the most by a reliever in franchise history.