At 26-18, Cincinnati has been a big surprise. The Reds blew a 4-1 lead but battled back in the eighth behind Barry Larkin.
Larkin opened the bottom of the eighth against Brad Lidge (0-3) with a triple. Houston Manager Jimy Williams elected to walk Sean Casey, the league's leading hitter, and Ken Griffey Jr., who earlier homered, bounced out to first.
But Kearns crushed his third homer of the season.
John Riedling (3-0) got the win despite allowing a tying two-run homer to Lance Berkman in the seventh.
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