"We feel like he's reached that point where he could be considered," Mattingly said before Tuesday's game against the Phillies.
Beachy is recovering from his second career Tommy John surgery and last pitched in a major league game on Aug. 20, 2013. On Monday, Beachy allowed five runs (three earned) on nine hits in six innings for Triple-A Oklahoma City, the fifth start of his minor league rehab assignment. But more importantly he was healthy and stretched out.
Beachy threw 93 pitches on Monday.
"He's feeling good today. The velocity is back to where it was in the past [before his surgeries]," Mattingly said. "That's one of the things we've talked about with Brandon, to give him the time to be right. Not only physically ready, but mentally."
Mattingly said Beachy touched 93 mph in his start on Monday night. The right-hander averaged 92.55 mph on his four-seam fastball in his 25 starts in 2011, then 91.83 mph in 13 starts in 2012, and 90.92 mph in five starts in 2013, per Brooks Baseball.
Depending on if Ian Thomas, recalled by the Dodgers on Tuesday, is used, he could conceivably be another candidate to start on Saturday as well. Eric Surkamp was optioned on Tuesday, so he would need someone to be placed on the disabled list in order to return within 10 days.
Mattingly said the decision on Saturday's starter hasn't yet been made.
"There are a number of guys again. We haven't really sat down and talked about it," Mattingly said. "I'm sure Andrew and Farhan are thinking about different guys and different combinations, and possibly the same type of game we had [Monday]."
With starter Carlos Frias on the disabled list with lower back tightness, the game Monday was a bullpen game of sorts, with Yimi Garcia starting for two innings, followed by Surkamp. Mattingly thinks the reaction to the decision was overblown.
"It's not really that much different. If we switch Yimi and Surkamp, it's really the same. One guy goes four or five, then from where we were sitting we knew we had to get two out of Yimi at some point," Mattingly explained. "It allows us to pinch hit that first time through."
The key to the plan though is having at least one pitcher go longer, at least four or five innings. The two times the Dodgers have tried this bullpen game, on June 2 in Colorado and on Monday, the long man didn't last very long, with Thomas pitching three innings in Colorado and Surkamp just 3⅓ on Monday.
"We have to have a guy available to throw a lot of innings," Mattingly said. "If a starter goes two innings, you're in trouble."