Dansby Swanson hit a three-run homer and the host Chicago Cubs edged the Houston Astros 4-3 on a frigid Wednesday night.
Both teams suffered in temperatures that, with the wind chill, felt like 33 degrees on the field at the start of the game.
The Cubs won for the eighth time in the past 11 games. The Astros, in last place in the American League West, took their fourth loss in a row and fell for the 11th time in the past 14.
The Cubs went up 1-0 on Michael Busch's sacrifice fly in the bottom of the first.
Two batters later, Swanson crushed a 2-2 cutter from Astros right-hander Spencer Arrighetti 369 feet through a stiff wind into the left field bleachers for a three-run blast, his third homer of the year.
The Cubs' big lead only lasted until the third inning, when Houston cut the margin in half with a small-ball rally.
Jon Singleton singled to lead off the frame. After a walk to Victor Caratini, Singleton scored when first baseman Busch made an errant throw after Jake Meyers dropped a sacrifice bunt to the mound.
Caratini scored on Alex Bregman's chopper to second base, pulling Houston within 4-2.
In the top of the ninth, Jose Altuve greeted former Astros teammate Hector Neris, the Cubs' closer, with a 390-foot, line-drive home run to left to slice the deficit to 4-3. It was Altuve's sixth long ball of the year.
Neris then retired Bregman, Yordan Alvarez and Kyle Tucker in order to register his second save as a Cub.
Chicago right-hander Jameson Taillon (2-0) worked 5 2/3 innings, allowing two runs (one earned) on seven hits with two walks and four strikeouts. He made 89 pitches.
Arrighetti (0-3), making his third major league start, lasted just 3 2/3 innings. He yielded four runs on seven hits and two walks with seven strikeouts in a 90-pitch outing.
The Cubs took the series opener 7-2 on Tuesday. The three-game set concludes Thursday afternoon.
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