Rapid Reaction: Cubs 3, Cardinals 0

How it happened: The Chicago Cubs got to Jake Westbrook and the St. Louis Cardinals early, when Starlin Castro singled and Anthony Rizzo doubled him home in the first inning. They added two more in the third, when Rizzo drove in Castro and Luis Valbuena with an opposite-field hit.

Edwin Jackson did his job on the mound, throwing seven shutout innings while allowing only three hits. The Cubs' bullpen finished the Cards off as Pedro Strop struck out Carlos Beltran with two on in the eighth, and Kevin Gregg earned his 16th save with a clean ninth.

What it means: It’s simply Jackson’s best start as a Cub. His pitches had movement throughout the night, keeping the Cardinals' hitters off-balance as he struck out five without giving up a walk. Every time he needed to make a pitch, he made one -- including his final pitch of the night, striking out David Freese with a man on third in the seventh.

On offense, Rizzo is starting to come around. His double to deep right-center was reminiscent of early-season plate appearances. Then he poked one to left in his second at-bat, proving he’ll go with the pitch when necessary. He hasn’t always done that. A prolonged slump might be over.

Outside the box: Brian Bogusevic returned to the lineup after missing several days with a hamstring injury. ... Michael Bowden was called up to take the place of Brooks Raley after the latter threw an extended relief stint on Wednesday. ... The decision on whether Travis Wood will participate in the All-Star Game will probably be made after his start on Sunday night. ... The Cubs have used a franchise-record 42 players before the All-Star break.

What’s next: Game 2 of the four-game series takes place Friday ,with Carlos Villanueva scheduled to take on Joe Kelly.