Lee came to the Marlins Wednesday in a trade that sent prospects Matt Dominguez and Rob Rasmussen to Houston.
Buehrle (8-8) held the Brewers to six hits and did not walk a batter, running his personal winning streak to three starts, during which he has struck out 22.
Milwaukee starter Mike Fiers (3-3) went 7 1/3 innings, giving up two runs on seven hits with one walk and nine strikeouts.
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