Dexter Fowler had a leadoff home run and two-run double in the first two innings and Dan Haren worked seven innings for the Chicago Cubs, who whipped the St. Louis Cardinals 9-0 on Monday.
The NL Central-leading Cardinals maintained a 5.5-game lead over Pittsburgh, which lost 3-1 to Cincinnati. The Cubs are 7.5 games back.
Addison Russell's three-run homer capped a five-run third that made it 8-0. The Cubs have won four in a row and got an 11-game trip off to a rocking start.
Haren (9-9) had five strikeouts and two walks. He contributed a single and sacrifice fly in Chicago's second victory in eight games in St. Louis this season.
Lance Lynn (11-9) surrendered six runs in 2 1-3 innings on nine days rest after getting extra time to recover from a sprained ankle in his last start.
The Cardinals are 3-4 on this homestand with two games to go. They're a major league-best 49-24 at Busch Stadium, but this was their most lopsided setback at home. They've been outscored 16-1 the last two games.
Fowler's leadoff homer was his fifth this season and the 14th of his career. Russell, the ninth-place hitter, hit his 13th homer in the third. The Cubs have five homers the last two games.
The Cubs are 36-29 on the road, second best in the NL behind the Cardinals' 38-27.