PITTSBURGH — Cubs left-hander Shota Imanaga appeared to wince after Pirates designated hitter Andrew McCutchen lined a double into left-center field leading off the sixth inning Tuesday night.

Manager Craig Counsell and head trainer Nick Frangella jogged to the mound, along with interpreter Edwin Stanberry. Imanaga eventually left the field with them, suffering from what Counsell specified as cramps in both quadriceps.

Though the diagnosis was minor and the Cubs won 9-0, Imanaga’s departure initially cast a shadow in the wake of Justin Steele’s season-ending elbow surgery this month.

“I did a couple of treatments, and there’s no issue now,” Imanaga, who improved to 3-1, said after the game.

He said he doesn’t anticipate the cramping will affect the timing of his next start.

“I feel like today, I was able to stop it a few steps before it would become a bigger issue,” he said. “I think it took some courage to say I should come out of the game, but I’m glad I did.”

Imanaga said he anticipated the cramping in the fifth and spoke to pitching coach Tommy Hottovy about it. It hit in the sixth during a seven-pitch at-bat against McCutchen when Imanaga’s fastball, which has averaged about 91 mph this season, dropped as low as 88.7, according to Statcast.

“I’ve experienced it a couple of times in the past with high humidity, and when my pitching’s going OK,” Imanaga said.

He had thrown five scoreless innings to that point, bouncing back from a far less dominant start last week against the Dodgers at Wrigley Field. That performance, which included five runs allowed on three homers, was overshadowed by a thrilling comeback as the Cubs walked off with an 11-10 win in 10 innings.

“There’s been a lot more of what we call the belt-line fastball,” pitching coach Tommy Hottovy told the Sun-Times. “When he’s great, he’s consistently getting the fastball up and the split down.”

In his mid-week bullpen session, Imanaga worked on honing the fastball at the top of the strike zone and practiced missing above it.

“He’s going to make mistakes,” Hottovy said. “But it’s just about trusting that he can get his fastball up there. The shape is great. Everything there is great. It’s just about getting the execution back up.”

The work essentially was a nudge back toward an approach the Cubs have always seen as the way to maximize Imanaga’s talents.

“He’s got the unique fastball that’s just hard to get on top of,” Counsell said. “And [when] you put it in that part of the strike zone, it’s even harder. For hitters to cheat to get on top of it — you can’t because of the [splitter].”

Last spring, Imanaga’s first playing in the United States, his main goal was figuring out the best use of his fastball in an unfamiliar league — and the Cubs stressed that the major-league strike zone stretched even higher than he might think. This year, coming off a rookie season that earned him a fifth-place finish in National League Cy Young voting, Imanaga has turned his focus to his slider, which he’s deploying at a higher rate — a tool to stay ahead of the other teams adjusting to him.

“We talked about that a lot this last bullpen,” Hottovy said. “Like, ‘OK, what about your delivery makes your fastball so good? We need to replicate that in the slider, not vice versa.’ ”

Imanaga’s fastballs against the Pirates were clustered at the top of the strike zone, a clear adjustment from the week before. Of the six hits he allowed, only the last was for extra bases.

“That’s what I worked on through the whole week, so I was looking forward to the outing,” he said. “And I’m glad it went well.”