The NL Central-leading Cardinals sent minor league outfielder Malik Collymore to their division rivals. St. Louis also received an unspecified amount of cash in the deal announced hours before the trade deadline on Friday afternoon.
The 31-year-old Broxton has struggled this season in Milwaukee. The right-hander is 1-2 with a 5.89 ERA.
Last week, St. Louis acquired another right-hander, former closer Steve Cishek from Miami, also for a minor leaguer.
The last-place Brewers continue to trade away veterans. They dealt outfielder Gerardo Parra earlier Friday to Baltimore for minor league pitcher Zach Davies.
Broxton and Parra were both acquired at last year's deadline by the Brewers, who were contending at the time.
