Casey Fien (1-0) worked two perfect innings to pick up his first major-league victory. Glen Perkins worked around Alcides Escobar's leadoff double in the bottom of the inning to pick up his fifth save in eight opportunities.
Blackburn, who was just recalled from Triple-A Rochester, held the Royals to one run and seven hits over 6 2/3 innings, while walking none and striking out two.
"I just finally put it all together," Blackburn said. "I was missing a lot of spots, but with movement as opposed to just floating it in there. One mistake hurt me tonight. Other than that I was pretty pleased with it."
Blackburn was demoted to the minors July 4 after going 4-5 with an 8.10 ERA in 13 starts and allowing 90 hits in 63 1/3 innings. After going 2-0 with a 2.57 ERA in two International League starts, he was recalled and replaced Brian Duensing, who was sent back to the bullpen after going 0-4 with a 10.13 ERA in four starts.
"That was a great performance," Twins manager Ron Gardenhire said. "It was desperately needed by him, for him. He made it look effortless.
"It's something he's been working on. He said he was going to stay light on his front side and let the ball come out of his hand. He did it with all of his pitches -- good changeup, good sinker and a good slider."
Blackburn did not reach a three-ball count on any of the 27 batters he faced.
"For the most part, I kept the ball on the ground and there wasn't a whole lot of great contact," Blackburn said. "I felt the movement was keeping guys off balance. It's definitely confidence boosting."
Greg Holland, the third Kansas City pitcher, worked out of a 10th-inning jam, which Nick Mastroianni led off with a triple to right.
Gardenhire said he was "disappointed" the Twins failed to get a run in the 10th, but run producers Mauer and Willingham came through in the 11th.
"It came down to the bullpens and a couple of big hits," Gardenhire said. "It starts off with Joe and Willie knocks him in. It's a couple of huge hits."
Luke Hochevar, the first overall pick in the 2006 draft, retired the last 10 batters he faced, and allowed five hits, all with two outs, in seven innings. He struck out six and walked none, throwing 67
strikes in 109 pitches.
"I'm just really encouraged with how he threw the ball," Royals manager Ned Yost said. "He was mixing his curve and got a couple of outs with his slider, and he located his fastball well."
Hochevar is 3-1 with a 2.68 ERA in his past seven starts.
Mastroianni homered in the second inning on a 3-1 pitch, the only run Hochevar allowed.
Twins reliever Jared Burton, who worked a scoreless eighth, has not allowed a run in his past 14 appearances, covering 14 2/3 innings.
The Royals have lost 14 of their past 18 games. .RHP Jeremy Guthrie, who was 3-9 with a 6.35 ERA in 19 games with Colorado, was acquired in a trade for LHP Jonathan Sanchez and will start Sunday for the Royals. LHP Everett Teaford, who was slated to start Sunday, will go to the bullpen as a long man. .Minnesota 3B Trevor Plouffe left with a bruised right thumb and is listed as day-to-day. Brian Dozier struck out as a pinch-hitter for Plouffe in the ninth inning. .Twins starters went 1-4 with a 6.51 ERA in their 2-5 homestand that ended Thursday. .LHP Scott Diamond, who won his only career start against the Royals, will start Saturday for the Twins. The Royals will counter with RHP Luis Mendoza, who has five quality starts in his past six outings.