Garrett Richards to replace injured Jered Weaver in Angels rotation

Garrett Richards didn’t care whether he pitched out of the rotation or bullpen; he just hoped the Angels would commit to one or the other so he wouldn’t have to go back and forth like he did last season, transitions that can tax the arm as well as the psyche.

Richards, the organization’s top starting pitching prospect, opened this season in the bullpen and emerged as a primary setup man, giving up one earned run and three hits in 41/3 innings in his first four appearances.

But when Jered Weaver was put on the disabled list Tuesday because of a broken bone in his left elbow, an injury that will sideline the Angels ace for four to six weeks, the right-handed Richards was moved to the rotation and tabbed to start Saturday against the Houston Astros.

And when Weaver returns? Richards, barring injury to another starter, will probably return to the bullpen.

“Because Garrett was stretched out as a starter in spring training, this shouldn’t be a difficult transition,” General Manager Jerry Dipoto said. “What you don’t want to see is this happening to a young player multiple times in a given year.

“But this is all hands on deck. We’re trying to win a championship, and Garrett understands that. You’re always going to have to scramble the jets when you lose a player who can impact the game like Jered.”

Richards threw 90 pitches in his last spring training start and is confident he could throw 100 on Saturday. He had the best spring of any Angels pitcher, with a 1-0 record and 1.45 earned-run average in six games.

“Long-term, I think they want me to be a starter,” Richards said. “It’s unfortunate what happened to Jered, but they asked me to step in, so I’m going to step in and do my job. When Jered comes back, we’ll move on from there.”

Domino effect

Richards’ move creates a hole in a bullpen that performed relatively well in Cincinnati and Texas, giving up six earned runs in 202/3 innings for a 2.61 ERA.

Right-hander Kevin Jepsen and left-handers Sean Burnett and Scott Downs will continue to set up closer Ernesto Frieri, but right-hander Mark Lowe, released by the Dodgers and signed by the Angels in late March, will probably assume a more prominent late-inning role.

Lowe threw four hitless innings in two games against the Reds but struggled with his command in Texas on Sunday, walking a batter and giving up a three-run home run to Ian Kinsler in the Angels’ 7-3 loss. Jepsen didn’t give up a run in three innings of his first four games but is limited to one-inning stints because of a lingering triceps issue.

“We’ll cover it,” Jepsen said. “It’s tough to lose an arm like Garrett’s, but filling Weaver’s role is more important.”

Short hops

The Angels began Tuesday’s home opener having sold the equivalent of about 22,000 full season tickets, about 2,000 less than they sold last season.

mike.digiovanna@latimes.com