Richards -- nearly eight months removed from rupturing his left patellar tendon -- struggled in a rehab start for Triple-A Salt Lake on Tuesday, giving up five runs on seven hits and four walks in five innings. He threw a bullpen session at Minute Maid Park on Friday, and the Angels will determine the next step on Saturday.
A Sunday start is still a possibility, though the Angels could also push him back to Monday or Tuesday.
"There's no doubt he's close," Angels manager Mike Scioscia said. "We'll make the best decision for Garrett, because the best decision for Garrett, in the long run, is the best decision for us."
Richards said all the runs he gave up on Tuesday came with two outs, attributing that to leaving pitches up and not executing on 0-2 counts.
"But that's just stuff that I have to do a little tweak on," Richards added. "It's not because of my knee. It's just things pitchers go through from time to time."
Prior to his most recent outing in Fresno, Calif., Richards gave up a combined two runs on 12 hits and seven walks in 24 1/3 innings in four intrasquad scrimmages and Minor League games during Spring Training, striking out 29 batters in the process.
The 26-year-old right-hander fielded a bunt and covered first base on Tuesday, and didn't experience any next-day soreness in his surgically repaired knee.
"I feel good," Richards said. "I feel like I can go out and compete at this level."
Some additional notes from Friday …
• The Angels denied a KABC report that they instructed stadium employees to work through the National Anthem, saying in a statement: "Our tradition is to have our stadium employees pause and join our fans in respecting and honoring the National Anthem. We will continue to uphold this practice for our stadium employees, which includes event staff such as ushers, gate personnel, event cleaners, merchandisers and concessions staff."
• Astros catcher Hank Conger faced his former team, the Angels, for the first time and called it "different," saying: "Obviously, you see the players and it's all the same, but once you see your staff on the other side -- I don't know, it kind of hit me. It's weird."
• Right fielder Kole Calhoun returned to the Angels' lineup Friday, after a right calf strain limited him to one pinch-hit appearance over the last four games. Matt Joyce started at designated hitter after fouling a ball off his right foot on Wednesday, which prompted Efren Navarro to start in left field and regular DH C.J. Cron to sit.