He got a lot of weak contact on his offspeed pitches and had six groundouts and struck out two over the next three innings before getting the third out of the sixth on a fly ball to center field by Yastrzemski.
McCullers has thrown 73 pitches. His highest pitch count this season is 92. The Astros, who are trying to snap a five-game skid, took a 6-0 lead on Martin Maldonado's homer in the sixth. The performance by McCullers comes after he tied a career high by allowing eight runs in just 3 2/3 innings of a 14-7 loss at Arizona in his last start.
The 26-year-old McCullers returned this season after missing last season recovering from Tommy John surgery.
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