CHICAGO — The Orioles watched a chance at a series split and their hopes of returning home above .500 disappear in a mess of a sixth inning. That spoiled what might have been Chris Tillman’s best start of the season and made the Orioles 5-2 losers to the Chicago White Sox on Thursday.

Tied at 1 entering the sixth, Tillman’s own narration of what happened was plenty succinct.

“Made a pretty crappy pitch to the leadoff guy, walked the next guy, I blow the bunt play,” Tillman said. “Then we get an out and did not do anything from there.”

The leadoff man in that inning, Matt Davidson, pestered the Orioles (32-33) all series and opened the inning with a double. Tillman issued his only walk of the day to the next batter, Yolmer Sánchez, before catcher Kevan Smith rolled a firm bunt between third base and the pitcher’s mound.

Tillman broke toward home and ran past the ball. Third baseman Manny Machado retreated to his base. Everyone was safe.

“It’s a play that Chris probably needs to make,” manager Buck Showalter said. “Manny made a good read on it, I thought. I thought Chris committed a little too much straight ahead. Knowing in that situation where they’re trying to bunt the ball, we’ve got to anticipate that a little bit better.”

Tillman recorded his season-high sixth strikeout once the bases were loaded, but ceded a two-run single to Melky Cabrera and exited the game.

Reliever Jimmy Yacabonis came in and threw 20 pitches — 13 balls — while walking three and allowing a sacrifice fly, with both of Tillman’s inherited runners scoring. He opened his fifth hitter with a ball and was pulled mid-batter by Showalter for Miguel Castro, who recorded the game’s last seven outs for the Orioles.

Showalter said Yacabonis “has had a track record of having command issues.”

Spoiled start: Catcher Caleb Joseph said he reminded Tillman after his last batter and again in the clubhouse that he did a “tremendous job.”

Even though he was tagged with five runs on 11 hits in 51/3 innings and took the loss to drop to 1-5, Tillman agreed.

“I think it’s much better, to tell you the truth,” he said. “A pitch here and there could have been better, but for the most part, it was a step in the right direction. … I felt real good, actually. Coming out of the bullpen, felt real good with all my pitches, both windup and stretch for the most part. Today felt good.”

Showalter saw similar improvement, which he has been badly hoping for from the typically steady veteran.

“I know it sounds very cliché-ish, but just about everybody’s outings worked off the fastball command,” Showalter said. “He was a little crisper, too. He really got down the line, not spinning off there. When he got out of whack with consecutive two, three balls, you’d see him spinning off his front side a little bit. It’s something he and [pitching coach Roger McDowell] have really been working on, and that’s something that’s really been a challenge for him, staying downhill.“

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