"He looks like the hard work has paid off," Francona said on Saturday. "The ball is just live out of his arm. You try not to get overly excited when you watch guys throw, but it's hard not to."
Carrasco, 25, missed all of last season while recovering from Tommy John surgery on his throwing elbow. This spring, the pitcher has no limitations, and he is up against Trevor Bauer, Scott Kazmir, Daisuke Matsuzaka, Corey Kluber and David Huff for the fifth spot in the starting rotation.
Carrasco is as intriguing a candidate as any of the others.
"There's a group of guys that are going to fight it out," Francona said. "I couldn't sit here and tell you I didn't want everybody to do well. I guess I hope we have tough decisions to make, but with his stuff, the ceiling is up to him."
Carrasco has gone 10-15 with a 4.93 ERA in 33 career starts in parts of three seasons (2009-11) with Cleveland. In 2011, the right-hander went 8-9 with a 4.62 ERA in 21 outings, during which he compiled 85 strikeouts and 40 walks over 124 2/3 innings.
During one five-start stretch from June 7-29 that season, Carrasco hit his stride, going 4-1 with an 0.98 ERA, 28 strikeouts and five walks over 36 2/3 innings. Directly following that run of success, he went 0-5 with a 7.92 ERA, 25 strikeouts and 17 walks in six outings (30 2/3 innings).
On Sept. 21, Carrasco went under the knife to correct the elbow injury.
"[This spring] will be a gauge for us to see if he's ready to try to help us win games," Francona said. "He's on the same path as everybody else right now. There's not a limit on him or anything like that. Shoot, he's ready to go."