After going through his normal pregame routine, Weaver, who has been on the disabled list since May 29 with a lower back strain, threw his full repertoire of pitches in a four-inning, simulated outing and said he felt no pain or discomfort afterward.
Manager Mike Scioscia said the plan is to have Weaver throw a bullpen session on Sunday, see how he feels, then have a discussion with the team's medical staff about when Weaver can return to the rotation.
"We want to make sure we don't miss any steps, and he's where he needs to be," Scioscia said. "Obviously, the first look out of the workout he felt great. We'll see how he feels tomorrow, play a little catch, and then Sunday throw a bullpen and see how he feels. Then we can make a determination of exactly where he is."
In 11 starts this season before going to the DL, Weaver (6-1) has a 2.61 ERA with 57 strikeouts and 15 walks. He's holding hitters to a .195 batting average. He injured his back in the first inning of the Angels' 9-8 win against the Yankees on May 28 while throwing a fastball to Robinson Cano.
In two starts replacing Weaver, rookie Garrett Richards (1-0) has given up three runs in 12 innings (1.50 ERA) with 12 strikeouts and seven walks. He is slated to start his third game of the season in the series finale against the D-backs on Sunday.