Brian Dozier had three hits for Minnesota, including a two-run homer in the ninth.
Deduno, making his sixth major league start, has given up just two earned runs and 10 hits in 19 1-3 innings.
Lester (5-9) had allowed 25 earned runs over his previous four starts and gave up only three runs and seven hits in eight innings on Thursday but was backed by just two hits against Deduno (3-0) and two relievers.
Adrian Gonzalez got both hits — a single and double — off Deduno, a minor-leaguer from 2005 until being called up by Colorado in 2010. Casey Fien retired the side in order in the seventh and Glen Perkins pitched two perfect innings for his sixth save in nine opportunities.
The Twins won for the fifth time in seven games, while the Red Sox dropped their second straight after winning four in a row.
ATHLETICS 4, BLUE JAYS 1
OAKLAND, Calif. (AP) — Josh Reddick hit a two-run homer to back another strong outing by Oakland's Bartolo Colon.
Brandon Inge and Seth Smith also drove in runs for the A's, who improved to 14-5 since the All-Star break.
Oakland moved past the Los Angeles Angels into second place in the AL West. The A's are 4 1/2 games behind Texas.
The Blue Jays have lost five straight, matching their season high.
Colon (8-8) scattered seven hits over eight shutout innings, extending his scoreless streak to 16 1-3 innings. The 39-year-old right-hander has not allowed a run since the fourth inning against the New York Yankees on July 22.
Colby Rasmus, Edwin Encarnacion and Yunel Escobar had two hits apiece for Toronto.
Henderson Alvarez (7-8) lost for the second time in six decisions. He had a season-high five walks, pitched with runners on base in all but one of his five-plus innings, and struck out one.
RANGERS 15, ANGELS 9
ARLINGTON, Texas (AP) — Josh Hamilton drove in four runs and the Rangers bailed out Ryan Dempster in his Texas debut.
The Rangers broke an 8-8 tie by scoring four runs in the seventh, including Hamilton's two-run double, and added three in the eighth.
Dempster allowed eight runs and nine hits in 4 2-3 innings. The Rangers acquired Dempster from the Cubs minutes before Tuesday's non-waiver trade deadline.
Roy Oswalt (4-2) threw two scoreless innings in relief for the win.
C.J. Wilson gave up eight runs and 10 hits in 5 1-3 innings. David Carpenter (0-1) took the loss for the Angels.
Ian Kinsler went 3-for-5 and scored four runs and Elvis Andrus and Michael Young had two hits and two RBIs each as Texas finished with 18 hits.
ROYALS 7, INDIANS 6, 11 innings
KANSAS CITY, Mo. (AP) — Alcides Escobar's RBI single with two outs in the 11th inning gave Kansas City the win.
Escobar's two-strike hit scored Eric Hosmer, who led off the inning with a single.
The Indians rallied from a six-run first-inning deficit, but lost their sixth straight, their longest losing streak since dropping seven in a row from June 19-26, 2010.
Aaron Crow (2-1), the sixth Royals pitcher, worked a spotless 11th inning to pick up the victory.
Reliever Esmil Rogers (1-1), the fifth of six Indians pitchers, took the loss. Carlos Santana homered and drove in four runs for Cleveland.
Indians right-hander Corey Kluber, who was making his first major league start, faced 10 batters in the first inning and gave up six runs, six hits and a walk, throwing 43 pitches. He made it through 4 1-3 innings, giving up no runs and three hits after the first.Suggest a correction