Mike Yastrzemski hit a tiebreaking pinch-hit double in the eighth inning and Mauricio Dubon followed with a two-run homer, helping the Atlanta Braves earn a 4-1 victory over the visiting Chicago Cubs on Wednesday.

JR Ritchie started for Atlanta, allowing one run on two hits, striking out four and walking three across 4 1/3 innings. Drake Baldwin also homered for the Braves, who won their fourth straight, secured a series victory and became the first team to reach 30 wins this year.

Raisel Iglesias worked around a leadoff walk in the ninth to post his eighth save in as many tries. Iglesias has yet to allow a run in 12 2/3 innings.

Shota Imanaga (4-3) tossed seven-plus innings, allowing two runs on five hits and no walks while striking out six in Chicago's fourth straight loss. Nico Hoerner had the lone RBI for the Cubs, who have mustered just three runs across their past four games.

Atlanta struck first, in the fourth inning. Baldwin belted a leadoff homer to center, his 11th long ball of the season.

Ritchie allowed Carson Kelly's single in the fifth and issued a one-out walk to Dansby Swanson, then was pulled after 87 pitches in favor of Tyler Kinley. Hoerner tied the game with an RBI single to left. Kinley retired the next two batters to preserve the tie.

The Cubs threatened in the eighth against Robert Suarez (4-0) with two outs as Alex Bregman singled and Ian Happ worked a walk. Suarez then struck out Seiya Suzuki to escape the jam.

Michael Harris II singled to begin the bottom of the eighth, chasing Imanaga. Ha-Seong Kim then singled off Phil Maton, who struck out pinch hitter Dominic Smith for the first out of the inning.

From there, Yastrzemski doubled to give the Braves a 2-1 lead. Kim was thrown out at home, but Dubon then socked a two-run homer to left -- his third of the year -- to push the advantage to 4-1.