Eric Show (6-6) has lost his last two starts while trying for the 93d victory of his career.
The Astros jumped to a 3-0 lead against Eric Show (7-10).
Cincinnati scored five times in the first three innings off Eric Show (0-1).
John Shelby led off the second with a single against Eric Show (5-7).
Eric Show (3-1) allowed four hits and three runs in seven and two-thirds innings.
Eric Show (10-10) pitched a six-hitter, winning for the fifth time in six decisions.
Benes now has 953 career strikeouts, surpassing the mark of 951 set by Eric Show.
Eric Show (1-4), who had shut out St. Louis in his last start, also went six innings and allowed five hits.
Eric Show (8-6) allowed six hits, struck out eight batters and walked four in pitching his first complete game of the season.
Eric Show got the last three outs for his first save of the season, and first since 1982.