ANAHEIM, Calif. — Nick Tropeano will become the second Los Angeles Angels starter this season to have Tommy John surgery, while ace Garrett Richards will continue stem cell treatments on his injured elbow after seeing positive results.

Los Angeles general manager Billy Eppler announced that after considering more conservative treatments — including stem cell treatments — Tropeano has elected to have surgery to repair his torn ulnar collateral ligament. Andrew Heaney had Tommy John surgery in July, and C.J. Wilson hasn't pitched all season due to various elbow and shoulder injuries, and was shut down July 5 to have shoulder surgery.

"Nick has decided to undergo UCL construction, so he will have Tommy John surgery," Eppler said. "We're still working on the date, but that will be in the near future. Right now, he's still deliberating over a couple physicians and we'll make that announcement when it comes to light."

Richards is still confident that he will not need surgery to repair his torn UCL after he was cleared to begin the next stage in his recovery. An imaging appointment with Los Angeles-based physician Dr. Steve Yoon showed continued healing in the injured ligament.

"The next course of action now will be to test the elbow and also to put him through some exercises," Eppler said. "In about 10 days to 14 days, he'll have a follow-up ultrasound and it will determine if he can pitch."

If further shows in the next round of imaging, Richards will be cleared to start a throwing program. He could potentially face live hitting as soon as September or October. Eppler said they are considering the Arizona Fall League or instructional league but he will not pitch in a winter league.

"I think that you still want to have him end this year and go into the winter with the feeling of having some answers, some questions answered, and not having to wonder if he will pitch and so on and so forth in spring training," Eppler said. "So I think if we can get him back up on the mound and get him pitching in a competitive environment, I think we would like to see that happen and I think Garrett will as well."

Richards echoed Eppler's sentiments.

"I think it's a must, I don't think there's any way I can not get into a competitive setting before this season is over," Richards said. "I need to get off a mound and throw 90-95 per cent for several pitches and full comfortable not only with myself, but make sure that my stuff is still there. Then I'll feel comfortable going into the off-season with what I have going."