Cubs 3, Cardinals 0: Anthony Rizzo knocked in all three runs and Edwin Jackson pitched seven strong innings against his former team as host Chicago won the opener of a four-game series with National League Central-leading St. Louis.

Jackson (6-10) turned in his best outing of the season, allowing only three hits and striking out five. Blake Parker got into trouble in the eighth before James Russell and Pedro Strop each recorded an out to strand two runners in scoring position. Kevin Gregg worked around his own one-out error and a two-out walk in the ninth for his 16th save.

Starlin Castro went 3-for-4 and scored twice for the Cubs, who have won five of six. Allen Craig had two of the Cardinals' four hits.

The Cubs did their damage early against Jake Westbrook (5-4), who gave up three runs on seven hits over seven innings. He was hurt by four walks.

Castro singled with one out in the first and scored on Rizzo's double into the gap in right-center. Rizzo knocked in Luis Valbuena and Castro with a single through the left side in the third.

GAME NOTEBOOK: Cardinals LF Matt Holliday left in the fourth inning after experiencing tightness in his right hamstring while running out a ground ball. Craig moved to left, with Matt Adams taking over at first base. … St. Louis C Yadier Molina went 0-for-4, lowering his NL-leading average to .339. … Castro recorded his first three-hit game since June 13 in a 14-inning affair against Cincinnati. This was his first in a nine-inning contest this season.