Lynn, who picked up the win, gave up six runs on eight hits over five innings. The Cardinals offense hit five home runs on the day and St. Louis took the lead for good on Matt Carpenter's solo shot in the fourth. Matt Holliday, Yadier Molina, Allen Craig and Lance Berkman also went yard.
Cubs starter Travis Wood, who gave up all five home runs, lasted five innings.
The Cardinals have won seven of their last eight games and stand eight wins above .500 for the first time since May 11.
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