The Chicago Cubs beat the Milwaukee Brewers 7-1 on Tuesday night. Here’s a quick look at the game.

How it happened: The Cubs scored four times in the first, as two errors by shortstop Elian Herrera opened the door for a big inning. Luis Valbuena and Jorge Soler had RBI hits. The Brewers got one back when Ryan Braun brought home Scooter Gennett in the third inning, but the Cubs broke it open in the fifth when a Welington Castillo RBI double was followed by an Arismendy Alcantara home run to right. It was his eighth on the year. Cubs starter Jake Arrieta went six innings and gave up five hits and a run while the Cubs pounded Brewers starter Yovani Gallardo. He gave up eight hits and five earned runs in five innings.

Castro hurt: Shortstop Starlin Castro left the game in the first inning after he slid awkwardly into home plate. The Cubs said he injured his ankle but didn’t fracture any bones. He was due for an MRI and was still under evaluation, according to the team.

What it means: The Cubs keep rolling, especially on offense. Even after losing Castro -- and already playing without an ailing Anthony Rizzo -- they crushed balls off of Gallardo. Even the outs, like a Soler blast to the wall in the fifth, were tagged. And all of a sudden Alcantara is sneaking up on double-digit home runs. Soler continued a hot streak with another RBI hit and barely missed another home run with the smash to left. The Cubs have started September the way they left off in August: winning.

What’s next: The Cubs go for the series sweep on Wednesday night when Kyle Hendricks (5-1, 1.91 ERA) takes on Matt Garza (7-7, 3.58).