HOUSTON -- A long two-run homer by Cubs slugger Anthony Rizzo in the first inning of Monday’s game wasn’t about to define Gerrit Cole’s day.

Cole responded to Rizzo’s 427-foot upper-deck shot into right field by sending down 17 of the final 19 batters he faced, finishing off a superb six-inning outing by striking out the side to record 12 punchouts in the Astros’ 6-5 win over the Cubs at Minute Maid Park.

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“I kept trying to make pitches,” Cole said. “It was a mistake to Rizzo, just a poor pitch over the middle. … I just brushed it off and kept going.”

Cole struck out the side in the third inning as well and pitched around a leadoff single in the fourth and a one-out single in the fifth. The Cubs never got a runner into scoring position against him after Rizzo’s 15th homer.

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“He just regrouped and completely dominated the rest of his outing,” Astros manager AJ Hinch said.

The Astros batted around in the third inning against Cubs starter Cole Hamels, scoring five runs to take a 6-2 lead. Houston held on in the ninth after closer Roberto Osuna gave up homers to Albert Almora Jr. and Addison Russell.

“[Cole] has got great velocity and carry,” Cubs manager Joe Maddon said. “If you could just not chase out of the zone on him -- he really relies on that. That’s a big part of what he does. The ball looks good and maintains its altitude and is hard to lay off of. For the most part, a lot of the strikes he gets are out of the zone, and you’ve really got to force him into the zone to get him.”

Cole entered the game one start removed from a loss against the White Sox, who scored six runs on seven hits over five innings against him. On Monday, he induced 26 swinging strikes to strike out 12 for the second time in four starts, and he leads the Major Leagues with 112 strikeouts in 71 2/3 innings.

“I just thought we were locating the fastball well today,” Cole said. “We were pitching to both sides of the plate and just overall executing a lot of good pitches. We had a good game plan and got a little bit of a lead early and that always helps you settle in and try to find the zone.”

Cole leads the Majors in double-digit strikeout games (six) and has walked three batters over 28 1/3 innings in his last five starts. The strikeouts are great, but Cole craves the increased efficiency to help him work deeper into games.

“When you get in a position to try to strike somebody out, you’re trying to strike ‘em out,” Cole said. “At the same time, I’d like to be getting into the seventh and eighth inning more often. Some of those strikeouts that are taking a few too many pitches are OK. Maybe it comes around to getting more efficient, and maybe there’s some bad luck with foul balls and guys having tough at-bats, but I have to keep executing and be more crisp.”