Manager Terry Francona finalized his starting rotation Wednesday, and it didn't include Bauer, the quirky, hard-throwing right-hander who led the American League in walks in 2015 but has had a very solid spring camp.
Bauer, who pitched six scoreless innings in his last outing, will be used in a relief role. Francona named Cody Anderson and Josh Tomlin the club's No. 4 and No. 5 starters behind Corey Kluber, Carlos Carrasco and Danny Salazar.
Indians president Chris Antonetti said the decisions weren't easy.
"We still expect all six guys to make a lot of meaningful starts," Antonetti said. "We used 11 starting pitchers last year. There are pitchers beyond these six that will make meaningful starts. To start the season, this was the way we felt was best for the team. Building on the success that Josh and Cody both had in the second half of the season, and what they were able to carry forward in the off season and spring, really led us down this path.
"It was a difficult decision, but the way we look at it is that we are in a pretty good spot to have six starters we feel so good about."
Francona said the 25-year-old Bauer did not take the news well.
"We completely respect that. I wouldn't be happy if I was him today. I don't blame him for that," Francona said. "What is important is handling it and moving on as a team. That's part of why we're here, not just to deliver bad news but put the best team in the field and be there when guys need help. Trevor has had a way when we've had difficult discussions, processing and coming back and going in the right direction."
Bauer went 11-12 with a 4.55 ERA last season, finishing the year pitching in relief. He's 17-22 in three seasons with Cleveland, which acquired him a three-team trade in 2012 from Arizona.
Tomlin had some struggles early in camp but recently found his groove. He pitched six scoreless innings with 10 strikeouts in a win over Seattle on Tuesday, a performance that may have sealed his spot in the rotation.
"It's a tough decision, but it's a good one," said Tomlin, who went 7-2 with a 3.02 ERA in 10 starts last season after recovering from shoulder surgery. "Them needing to make tough decisions are a good thing on our part, I feel like. I'm hoping for the best 25 guys. We want the best 25 guys to go out there and win. We need to put personal preferences aside. You do whatever you can to help your team win games. The goal should be to try to win the World Series, not I'd rather start, I'd rather be in the bullpen.
"Just get the ball whenever you get the ball and try to compete and win."