ARLINGTON -- Royals right-hander Homer Bailey made the same costly mistake Saturday that Friday’s starter, Danny Duffy did: he put a pitch in the wrong place against Rangers slugger Joey Gallo.

As in Friday’s loss, Gallo’s homer broke the Royals; this time it was a two-run shot instead of a grand slam, but it represented the go-ahead runs in another 6-2 loss at Globe Life Park. Gallo’s fourth-inning homer traveled 431 feet, per Statcast, and breezed over the bullpen in right-center.

“Don’t make a mistake on him,” Royals manager Ned Yost said. “He’s big, and he’s strong. We talk about elevating pitches, [and] the pitch wasn’t elevated enough. We at times can pitch him up and it was at the belt, and it wasn’t in enough. But he’s a strong guy. You make a mistake, and he’s going to hit it out of the ballpark.”

• Box score

Bailey extended a concerning recent trend on Saturday with another short outing, the fourth consecutive start he has exited early. He left after 3 2/3 innings and four earned runs, and he hasn’t pitched more than 4 1/3 innings since May 10. The Royals have lost the past four games he started, and his ERA over that stretch ballooned to 9.64 after Saturday.

“There were some pitches there that I thought we made fairly well that were ground balls through the infield,” Bailey said. “Obviously, the one to Gallo -- I probably could've gotten inside a little bit more on that one. I made some pretty decent pitches, and they just found holes.”

Hunter Pence led off the game’s most consequential inning with a grounder to right, setting up Gallo. Jeff Mathis lifted a sac fly, and Shin-Soo Choo ripped an RBI double to run the score up to 4-0. Choo was Bailey’s final hitter.

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“It was a little reminiscent of last night,” Yost said. “It just kind of kept avalanching on [Bailey] from that point, five hits in the inning, and he got his pitch count up to around the 80-pitch mark and just was really laboring at that point.”

The Rangers’ leadoff hitter reached in each of the last three innings Bailey started. He issued walks to Gallo and Mathis to begin the second and third frames.

“You want to go out there and get the first person of the inning, and that was probably something that we could have done a lot better,” Bailey said.

Gallo was removed from the game due to left oblique tightness in the middle of his next at-bat after the homer. He will undergo an MRI and probably won’t play in Sunday’s series finale, but he has already shown Yost what kind of impact he can have on a series. Yost said he thinks Gallo has improved considerably since last season.

“There’s a big difference,” Yost said. “He’s more disciplined this year. He’s kind of coming into his own here. You look at his numbers. He’s hitting .314 against lefties going into the day. Last year, that wouldn’t have been the case. He’s just growing into a pretty darn good run producer. He was a high-strikeout guy last year, a guy that you knew if you made a mistake, he’d catch ahold of it. But he’s becoming a more well-rounded hitter.”

After Bailey left, Wily Peralta got the last out of the fourth inning and then Brian Flynn pitched four yeoman-like innings, scattering five hits and allowing one earned run, to save the Royals’ bullpen.

“He did a nice job,” Yost said. “With [starter Brad] Keller going tomorrow that gets us right back on track. We’re pretty full, locked and loaded.”

The Royals’ offense was unable to break through against Rangers starter Lance Lynn, who yielded two earned runs in 6 1/3 innings.

Kansas City has dropped the past two games of the four-game series against the Rangers, which began with a Royals victory on Thursday. The Royals have lost 22 of their last 33 games.