Angels’ left-hander C.J. Wilson is out indefinitely because of shoulder issue

C.J. Wilson said his surgically repaired throwing elbow feels “great,” but the adjustments he made to compensate for the injury have led to a shoulder problem that could knock the Angels left-hander out for the first month of this season, maybe more.

Wilson, diagnosed with shoulder inflammation early in camp, suffered another setback in a bullpen session Saturday and will be relegated to catch and long toss. No date has been set for a return to the mound.

“When you have stuff going wrong in your shoulder, there’s only two ways to fix it — you either rehab or you have surgery,” Wilson said. “We’re obviously rehabbing it because I’m going to pitch. … But it doesn’t do me or the team any good to pitch if I’m not going to be effective.”

Wilson hasn’t pitched in an exhibition game or faced hitters this spring. Once he returns to a mound, he will need at least four weeks to build up the stamina to throw 90-100 pitches in a game, a process that could push his return to late April or May.

Wilson, 35, said he is taking “massive amounts” of anti-inflammatory medication, undergoing physical therapy and treatment and studying video to pinpoint the mechanical flaws that are putting stress on his shoulder.

Wilson, who went 8-8 with a 3.89 earned-run average in 21 starts before being shut down in August because of bone spurs in his elbow, said he is “not going to get into a game any time soon.”

Having had reconstructive elbow surgery in 2003 and three operations to remove bone spurs in his elbow, Wilson won’t rush his return.

“I don’t really care how long it takes to get back to the level I want to get back to,” said Wilson, who is in the final year of a five-year, $77.5-million deal that will pay him $20 million this season. “If it takes an extra three or four weeks, it’s better than going out there, being substandard and getting my head knocked off.

“I’m not trying to be selfish about it. It’s not an ego thing at all. The team deserves to have the best version of me possible, and all I’m trying to do is be that guy.”

The Angels entered camp with eight major league-ready starters, but that depth has thinned considerably, with Tyler Skaggs and Jered Weaver likely to open the season on the disabled list. Barring further injury, they will open with a rotation of Garrett Richards, Andrew Heaney, Hector Santiago, Matt Shoemaker and Nick Tropeano.

mike.digiovanna@latimes.com

Twitter: @MikeDiGiovanna