CHICAGO -- The Kansas City Royals lost their starting pitcher in the first inning and were in the middle of a listless day at the plate before Johnny Giavotella turned it all around with one big swing.

Giavotella hit a two-run double off Matt Thornton in the seventh inning and Jeff Francoeur belted his first homer of the season, leading the Royals to a 9-1 victory over the Chicago White Sox on Sunday.

"We were dead and (Giavotella) put up a huge at-bat against a guy who's not easy to hit and throws 97," Francoeur said. "So I thought that kind of livened us up and then we were able to relax and have some good swings."

Alcides Escobar went 3 for 3 with two walks for Kansas City, which broke it open with six runs in the ninth inning. Francoeur also had an RBI single and made a nice play in right field.

Kansas City won for the fourth time in five games despite losing Danny Duffy to elbow tightness after just three batters. The left-hander recorded two outs before catcher Humberto Quintero saw him shake out his arm at the end of a throw, prompting a mound visit from manager Ned Yost and a trainer.

"As soon as he said 'It's in my elbow,' I said 'That's it,'" Yost said. "We need to get that checked, see what's going on there, and go from there."

Duffy was headed back to Kansas City on Sunday night and is scheduled for an MRI exam on Monday. He also experienced tightness in his elbow last month.

"You can't worry about things like this until you know what it is," Duffy said. "My main concern was letting down my team. These guys are my brothers in here. They did a great job of picking me up."

Luis Mendoza came in and pitched 5 2/3 innings, keeping the Royals in the game while they struggled to score against Philip Humber. Mendoza (2-2) allowed one run and seven hits, struck out four and walked two.

"Just tried to get that confidence," he said. "I mean the last three appearances, I feel good and more confident, too."

Humber broke out of his post-perfect game slump, pitching four-hit ball into the seventh inning, but the White Sox still lost for the fourth time in their last five home games.

Humber walk Escobar with one out in the seventh, but got Quintero to foul out before he was replaced by left-hander Matt Thornton (1-3) with the White Sox clinging to a 1-0 lead.

Jarrod Dyson then walked, and both runners moved up on a wild pitch. Giavotella followed with a double down the right-field line, giving the Royals the lead with his first hit of the season. He is 1 for 10 in four games since he was recalled from Triple-A Omaha on Wednesday.

"I was glad to be a spark," Giavotella said. "We couldn't score against Humber. He was keeping us at bay, so I'm glad I was able to get a big knock for us."

Humber struck out seven and walked three in his best start since his gem at Seattle on April 21. The 29-year-old right-hander was 0-2 with a 13.50 ERA in his previous three outings.

"Definitely a step in the right direction," he said.

Francoeur hit a drive to left off Nate Jones in the eighth for his first homer since Sept. 23 at U.S. Cellular Field. He also made a nice sliding catch on Brent Morel's drive to the warning track in the fourth before nearly doubling off Tyler Flowers with a strong throw to first.

The White Sox put runners on first and second with one out in the eighth but Kosuke Fukudome struck out and fellow pinch-hitter A.J. Pierzynski bounced out to end the inning.

"We've been leaving guys on base, we had opportunities today," manager Robin Ventura said. "We have guys that are swinging OK, it's just not coming through. You have to continue to grind. I know they're going to work and go at it."

Game notes:

White Sox LHP Chris Sale said he felt fine one day after his first start since May 1. "Everything went well today," he said. Sale was moved to the bullpen because the team was concerned about his sore elbow, but he talked his way back into the rotation after an MRI came back clean. ... Royals 3B Mike Moustakas (sore left hamstring) rested for the second straight day. "Just one more day," Yost said. "Playing cautious with it." ... Ventura said he wants to keep Adam Dunn in the lineup when they face the crosstown Cubs at Wrigley Field next weekend, and he's leaning toward playing the burly slugger in left. "Plus he'll enjoy the fans out in the outfield," Ventura said with a grin. "He likes to talk. He likes fan interaction." ... The Royals open a two-game series at AL West-leading Texas on Monday. LHP Bruce Chen (1-4) is scheduled to face Rangers RHP Scott Feldman (0-0). ... Chicago hosts Detroit in the opener of a two-game series on Monday. White Sox LHP John Danks (2-4) is slated to face LHP Drew Smyly (1-0). ... White Sox reliever Jesse Crain (oblique) threw a scoreless inning in his second rehab appearance with Triple-A Charlotte.