Angels’ Garrett Richards hoping for a return in August

While the Angels roam around .500, their best pitcher waits, sentenced to inaction by a rare condition within his prized right arm to which there is no known cure besides time.

The cutaneous nerve in Garrett Richards’ biceps remains irritated, preventing him from firing off his 97-mph fastballs. He did so for one dominant game last month but exited five innings in with what the team termed a biceps cramp. A subsequent MRI examination demonstrated the problem, which continues to date.

When can he come back?

“I don’t know,” Richards said Saturday at Angel Stadium. “September, if anything, maybe. It’s gonna come back when it wants to come back.”

Examining the season’s six-month docket the Angels have painted on one of their clubhouse walls, Richards clarified that he retains hope to return in August.

“Looking at the schedule right now, I think that’s realistic,” he said. “I think that’s all going to depend on when I start throwing again. But with the past cases, this was like a one-time thing for these guys. So I’m hopeful on that, too, that this might just be a fluke thing and I just continue on.”

Team doctors made Richards aware of two cases similar to his. In 2004, right-hander Brad Penny felt biceps nerve irritation shortly after the Dodgers acquired him at the trade deadline and effectively missed two months. That same year, St. Louis right-hander Chris Carpenter missed the season’s last two weeks and the Cardinals’ World Series run with the same condition.

“What I’ve been told is theirs were worse than mine,” Richards said. “So, if it took them all offseason to get back for spring training, then hopefully mine’s shorter than that. That would give me a chance to pitch this year.”

Richards, 28, experiences no pain in the muscle at all, only weakness.

“Literally, in my mind,” he said, “I’m like, ‘I don’t know why I’m hurt.’ ”

So, after much of the same last season while waiting for a stem-cell injection to regenerate his torn elbow ligament, he is again left to battle his body and his mind.

“I’m just waiting,” he said. “That’s really all that I can do. It’s made progress since it happened, but it’s taken six weeks to get there.”

Richards said he has lately noticed “considerable jumps” in the weight room. He’s up to curling 20 pounds with his right biceps, compared to 35 with his left. Periodically, the club tests the strength of the muscle with other exercises.

He cannot pick up a baseball until the two sides are equally powerful.

“The biceps slows down the elbow,” Richards said. “So, if it isn’t strong, the elbow is just gonna be shredded, especially with my velocity and my arm speed.”

The Angels have researched other possibilities to help him recover and produced nothing concrete, because there is no precedent for outside treatment. They hope that when he is cleared to throw again, he can progress quickly.

“Once he’s 100%, he’s probably already gotten some of the legwork and questions out of the way, compared to where he was in the spring,” manager Mike Scioscia said. “Hopefully that build-up will happen in a more timely fashion than our seven-or-eight week spring training.”

Until then, Richards works out and waits. And, when the Angels go on the road, he creates a hitter on the “MLB: The Show” video game and tries to hit homers.

“Every day that goes by, I’m missing an opportunity,” Richards said. “It’s really hard to deal with. But what are you gonna do? Hopefully, if I can come back with a couple months left in the season and help us toward the end, it’d be like an instant boost, and you don’t have to go find somebody.”

pedro.moura@latimes.com

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