KANSAS CITY, Mo. -- Bruce Chen was hardly fine. Thanks to the Kansas City hitters, he didn't need to be so sharp.
Betancourt had a two-run single in the fourth inning and hit his 12th homer, which is career high, in the sixth as the Royals took a 9-4 lead. He has hit .421 with 10 RBIs in his past 11 games.
Mitch Maier hit a two-run triple and Billy Butler also drove in a pair of runs for Kansas City. Gregor Blanco added two doubles.
It was the Royals' highest-scoring game since a 10-3 win over St. Louis on June 27.
"Every bit of the order we had offensive production," Royals manager Ned Yost said. "All and up down the lineup it was a good night offensively. Bruce did a pretty good job and got us into the sixth. His command fluctuated a little bit, but he did enough to get the big out when he needed."
Chen (8-6) benefited from the Royals' offensive splurge to win for the third time in four August starts. He gave up four runs on 11 hits in 5 2/3 innings.
"Both teams were swinging the bats real well." Chen said. "I tried to make good pitches and pound the strike zone. Luckily, I was able to minimize the damage so we could win. I was making good pitches when I needed."
Chen went 1-13 with three big league clubs from 2006-09 and missed the 2008 season after elbow surgery.
"I've gone through a lot of ups and downs," he said. "I've never given up. I feel like I'm having a good year. I like playing this game. I feel like I can keep pitching at this level."
Fausto Carmona (11-11) fell to 1-4 in his past five starts. He allowed seven runs on nine hits, a walk and a hit batter in five innings.
"The problem tonight was getting the ball up," Carmona said. "I gave up a lot of base hits on sinkers. Every pitch was up - the sinker, the changeup, the slider. I got a couple of ground balls with the sinker, but they were hit where nobody could catch them. Everything was up."
Joakim Soria gave up a single and walk in the ninth, but held on for his 35th save, which ties for the American League lead, in 37 opportunities.
Asdrubal Cabrera and Shin-Soo Choo each had three hits and drove in two runs for Cleveland.
Choo's double in the three-run eighth scored Michael Brantley and Cabrera, trimming the Royals' lead to 9-7. The Indians had 17 hits, but stranded 11 runners.
"Hits don't win games," Indians manager Manny Acta said. "Hits with runners in scoring position win games. We put up a fight at the end but it was not enough. Sometimes you get less than that and score more. It's been a struggle for us. It's not how many hits you get, it's how many runs you score, but we scored enough runs. We just didn't pitch well."
Shelley Duncan led off the Indians' second with his seventh home run, snapping an 0-for-19 slump. Chris Gimenez's double in the sixth scored Jayson Nix and Jason Donald.
Billy Butler grounded into his major league-leading 26th double play in the third inning, tying a Royals single season record. John Wathan grounded into 26 double plays in 1982.
Kansas State basketball coach Frank Martin threw out the ceremonial first pitch. ... OF Jai Miller, who appeared in one big league game June 22, 2008, with the Florida Marlins, joined the Royals after his promotion from Triple-A Omaha, where he hit .365 with six home runs and 15 RBIs in his past 14 games. ... DH Travis Hafner, who had two hits and two walks Tuesday, was not in the Indians lineup Wednesday. "It's a planned day off against a lefty," Acta said. "We'll play him the next four games." ... The Indians plan to promote blue-chip pitching prospect Carlos Carrasco soon from Triple-A Columbus. "He is a September callup and we may want to look at him before then, maybe later this month," Acta said. "I'm anxious to take a look at him. He's definitely a part of our future." He is 10-5 with a 3.71 ERA in 23 International League starts.