Mike Tauchman hit a game-tying, two-run double in the ninth inning, then scored the go-ahead run on a throwing error by Milwaukee third baseman Brian Anderson as the Chicago Cubs rallied for a 4-3 win over the host Brewers.
Chicago trailed 3-1 entering the ninth and faced All-Star closer Devin Williams (4-2), who had converted 18 of 19 save opportunities entering the contest.
Cody Bellinger, who earlier extended his hitting streak to 11 games, led off by hitting a single to center. Jared Young then reached on a one-out infield single, and both runners advanced one base on Yan Gomes' grounder.
Then Tauchman, who fouled off four of Williams' pitches, dropped a liner inside the left field line to tie the contest. He then scored from second when Anderson's throw on Nico Hoerner's grounder short-hopped first baseman Owen Miller.
Adbert Alzolay then retired the side in order in the ninth for the Cubs, who built off Tuesday's 7-6, 11-inning win to take two of the first three games in this four-game set.
Justin Steele's three-start winning streak ended after allowing three runs and nine hits in six innings for Chicago, which has won two in a row for the first time since a four-game winning streak from June 19-24.
Willy Adames clubbed a tiebreaking homer off Steele in the sixth inning, and Anderson added an RBI single later in the frame for a 3-1 Milwaukee lead. Christian Yelich and Andruw Monasterio each had two hits, and Adrian Houser allowed one run on six hits and three walks over five innings.
Seiya Suzuki had three hits for Chicago, which opened the scoring on Ian Happ's third-inning RBI single. However, Milwaukee answered in the bottom of the frame thanks to William Contreras' two-out, run-scoring single to right.
Michael Rucker (2-1) got the win for Chicago.
Chicago All-Star shortstop Dansby Swanson, who grounded into two double plays on the night, exited prior to the bottom of the seventh due to a left heel contusion.
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