Dallas Keuchel had worked hard to erase his unsightly first inning, keeping the Twins muzzled with ground ball after ground ball and limited foot traffic.

But on his second-to-last batter, with two outs in the sixth, Keuchel undid several innings of goodwill by allowing a two-run homer that proved costly in a 4-3 loss at Target Field on Tuesday night.

In fairness to Keuchel, the pitch hardly looked like it was destined to leave the yard. It was a lower-third cutter, inside and off the plate, but Willians Astudillo didn’t mind. He dropped to a knee and barreled it into the left-field bleachers.

Trying to protect a one-run lead, Keuchel had lost Miguel Sanó on five pitches in the previous at-bat. Then he yanked a first-pitch sinker well out of the zone, prompting catcher Seby Zavala to go out to the mound for a quick chat.

“I was like, ‘Let’s go cutter deep in,’” Keuchel recalled saying to Zavala. “Which, I mean, the pitch was three or four inches inside, so you kind of just got to tip your cap to [Astudillo]. And then we were going to go changeup away to hopefully get him to roll over. Just didn’t get to that third pitch. I mean, I didn’t think something like that was going to happen.”

That’s right, the “deep in” cutter was meant to be a setup pitch, one that would ideally make Astudillo overeager for a changeup to follow.

Keuchel doesn’t regret his execution, it’s just that his opponent had other plans.

“You’re really never sure what he’s going to do,” Twins manager Rocco Baldelli said of Astudillo. “Sometimes he does more damage on pitches six inches above the zone, or in, or down, you really don’t know.

“​​He’s a guy that does cover different areas in unique ways and can throw some loops at the opposing team and the opposing pitchers.”

If not for that hit, Keuchel was on his way to salvaging an outing that began with a two-run, 28-pitch first inning. He walked three of his first four batters, filling the bases before allowing an RBI single and groundout, which put the White Sox in an early hole. From there, though, Keuchel went on a run in which he retired 15 of 18 batters, with no more than one occupying the basepaths at a time.

When something’s off, there are ways to regain your rhythm mid-game, Keuchel said. He did look at video of a few of his pitches between innings, but he typically likes to work out his kinks on the mound. Tuesday’s issue was with his “connection point,” meaning the part of his delivery where his front foot lands and the ball is released.

He only garnered one strikeout -- something he’s done three other times this season, all in outings of five-plus innings -- while collecting 10 ground-ball outs. And after retiring the first two hitters in the sixth, he was on the cusp of walking away with a quality start and a 3-2 lead.

Instead, Keuchel walked Sanó, and Astudillo roped a two-run shot on a pitch Keuchel didn’t expect him to hit. The White Sox had a pair of homers themselves, with Adam Engel and José Abreu going back-to-back in the third inning, but that accounted for all of Chicago’s offensive production.

The White Sox entered with 7.1 runs scored per game against the Twins this season (in 17 games), but this time the offense couldn’t bail Keuchel out. In fact, he hasn’t been bailed out much lately: Since June 20, Chicago is just 2-7 in games he started.

Not that Keuchel is looking elsewhere to pass the blame. He owns a 5.74 ERA in that span, and he knows he needs to be better than that.

Keuchel was better Tuesday, at least for most of the night. But an inexplicable home run sunk him nonetheless.

“I feel like if I didn’t have bad luck right now, I wouldn’t have any luck at all,” he said.