The Indians said Wednesday that Carrasco will start on April 5 against Minnesota.
The 27-year-old Carrasco made five trips to Cleveland in 2013, bouncing between Triple-A Columbus and the majors. The right-hander was 1-4 with a 6.75 ERA, but played a key role out of the bullpen during the Indians' stretch run to a playoff spot.
''There were numerous reasons, but it was difficult,'' manager Terry Francona said. ''We were open about saying we really wanted to see Carlos pitch. We can't build our team just for opening day. Josh will help us at some point.''
Tomlin is recovering from elbow reconstruction surgery and has options. The Indians want him to get consistent work in the minors, rather than working out of the bullpen.
''We thought about putting Josh in the bullpen, but that wouldn't be fair to him,'' general manager Chris Antonetti said. ''There is not a lot of development with Josh. He just needs consistent work. There are no set innings for him but we will monitor him, looking for signs of fatigue. We talked to him about his workload issues. He was very professional when we told him.''
Aaron Harang and Trevor Bauer were also competing for the rotation spot.
Harang was released and signed with the Atlanta Braves. Bauer was optioned to Columbus on March 24.
The Indians will carry 13 pitchers, eight in the bullpen.
Scott Atchison got a spot in the Indians' bullpen as a non-roster player. Blake Wood was told he'd won a place as well.
''Scott has the ability to pick up innings or get big outs when you need them,'' Francona said. ''Blake's stuff is off the charts. He had a really good camp. We asked him to get better at holding runners. He not only got better he exceeded our expectations. Now he is quick to the plate and will be tough to run on.''