Mondesi's third hit, an RBI single with two outs in the seventh, scored Whit Merrifield to make it 5-4. Mondesi had hits in three straight at-bats to end an 0-for-11 skid. He also scored on Jorge Soler's RBI double to make it 6-4.
After Homer Bailey pitched six-plus innings of three-run ball, Brad Boxberger(1-3) allowed a run in the seventh but still got his first victory in 26 appearances. Ian Kennedy pitched the ninth for his fourth save in six chances.
Jace Fry (1-2) took the loss.
Ivan Nova allowed four runs in 5 1/3 innings with six hits and a season-high six strikeouts.
James McCann put Chicago up 2-0 with a two-run double in the third, but Kansas City got one back in the bottom of the inning on Whit Merrifield's RBI single.
Merrifield sparked a three-run sixth with a leadoff infield single. Alex Gordonsingled against the shift and Mondesi tied it with a double to right. Nova then walked O'Hearn, snapping a streak of four straight strikeouts for O'Hearn, and Nova was done.
Cheslor Cuthbert ripped a single into right, scoring Gordon and Mondesi to give Kansas City a 4-2 lead. He has hit safely in all seven games since being called up May 31.
White Sox: OF John Jay was transferred to Triple-A Charlotte for his rehab assignment. He has been on the IL with a right hip strain since spring training. He played three games with Double-A Birmingham and went 2 for 10.
Royals: 3B Hunter Dozier is making progress in his recovery from strained oblique. He is getting closer to introducing some baseball activity. He's eligible to come off the IL for Tuesday's game against Detroit but said he probably won't be ready for that. ... LHP Danny Duffy, who was hit by a line drive in Thursday's start against Boston, said before Friday's game that he is sore but doesn't think he'll miss a start.
The White Sox will send RHP Lucas Giolito (8-1, 2.54 ERA) to the mound in the second game of the series. Giolito was the AL Pitcher of the Month for May. He is 7-0 with a 1.92 ERA over his last nine starts.
The Royals will depend on RHP Brad Keller (3-7, 4.50 ERA). Keller has faced the White Sox three times already in 2019.
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