Carlos Santana hit a three-run homer in the first off Ubaldo Jimenez (4-9) and Michael Brantley added a two-run shot in the fifth as the hot-and-cold Indians won for the fifth time in six games. Jimenez, who pitched the Indians to the postseason in 2013, lost to his former teammates for the second time this season.
Carrasco (5-4) got two inning-ending double plays to avoid early trouble and then retired 15 straight after giving up a leadoff double in the third.
The Orioles have lost consecutive games for the first time since June 28-29.
Inconsistent starting pitching has been a problem for the Indians all season, and manager Terry Francona has been waiting for someone to step up.
Carrasco could be the guy.
The right-hander hasn't allowed a run or walk in 12 consecutive innings.
Carrasco has bounced in and out of Cleveland's rotation this season. He's always had electric stuff and the Indians have held out hope he would figure things out. He threw five shutout innings against the Yankees last week, and if he continues to pitch the way he has lately, he'll hold onto a starting job for a while.
Cleveland's unreliable defense the Indians lead the majors in errors turned double plays to end the first and second innings behind Carrasco. In the ninth, right fielder Chris Dickerson ran down Steve Pearce's shot to the track, robbing him of extra bases and preserving the shutout.
Santana staked Carrasco to a 3-0 lead in the first with his 21st homer, a 422-foot shot to straightaway center.
Jimenez came in leading the AL in walks, and he struggled to find his release point while putting Michael Bourn and Jose Ramirez on to start the inning. One out and a passed ball later, Santana made his former batterymate pay with a towering blast into the shrubs behind the center-field wall.
Brantley's 18th homer capped a three-run fifth to make it 6-0.
Jimenez spent two-plus seasons with Indians, who acquired him from Colorado at the trade deadline in 2011. The 30-year-old had his good and bad moments, but he saved his best for last September, when he went 4-0 with a 1.09 ERA in six starts and helped the Indians clinch a playoff spot.
Jimenez cashed in on that run, signing a four-year, $50 million free agent contract with the Orioles in February.
But he's been pounded by the Indians in two starts this year, allowing 11 runs and 10 hits in 8 1-3 innings.
Orioles: CF Adam Jones played despite soreness in his right hand, which was hit Friday night when he tried to get down a bunt in the eighth inning.
Indians: Bourn returned to center field and the leadoff spot after being sidelined since July 6 with a troublesome hamstring. He went 0 for 2 with a walk, sacrifice and scored once.
Orioles: RHP Kevin Gausman, 2-1 with a 3.21 ERA in five starts, will try to salvage the series finale. In his only previous outing against the Indians, he took the loss in relief on Sept. 4, 2013, allowing two runs and three hits in 2 2-3 innings.
Indians: Enigmatic RHP Danny Salazar will be recalled from the minors to make his 13th start. The hard thrower has battled mechanical issues this season, which began with him in the rotation. Salazar is 4-0 with a 2.79 ERA in seven starts in which he has pitched at least five innings.