Scherzer (15-1) allowed just a second-inning double to Darin Ruf in the dominating victory on his 29th birthday, lowering his ERA to 3.01. The right-hander didn't allow a walk and struck out seven.
He became the first Tigers pitcher to win 15 of his first 16 decisions since George Mullin in 1909.
Miguel Cabrera smashed his 32nd homer of the season -- a solo shot in his first at-bat after missing four games with an injury -- and finished with three RBI, while Matt Tuiasosopo added a three-run blast for American League Central-leading Detroit.
Raul Valdes (1-1) was pounded for nine runs on 12 hits over 3 2/3 innings for the reeling Phillies, who dropped a seventh straight.