The decisive blow was Pham's second home run of the season -- a 371-foot drive to left on a full count off Padres starter Jordan Lyles in the fifth inning.

Pham's homer gave the Cardinals a 2-0 lead. Padres catcher Raffy Lopez halved the deficit with his second homer of the season on a full-count pitch from Mikolas in the seventh.

Mikolas, who began his career in the Padres organization, allowed the one run -- on Lopez's 411-foot drive to center -- on five hits and a walk with four strikeouts in 6 2/3 innings. Mikolas is now tied for second in the National League in wins and sits eighth in the league with a 2.51 ERA.

Jordan Hicks got the last out in the seventh inning, and Greg Holland tossed a scoreless eighth. Bud Norris picked up his eighth save with a perfect ninth inning.

Pham hustled the National League Central-leading Cardinals a quick 1-0 lead in the first, scoring an unearned run off Lyles, who was making his first start of the season after 13 relief appearances for the Padres.

Pham singled to open the game, moved to second on a Lyles wild pitch and to third on a passed ball by Lopez. After Lyles struck out Matt Carpenter, Pham scored easily on Jose Martinez's sacrifice fly to center.

Pham, Marcell Osuna and Paul DeJong each had two of the Cardinals' eight hits.

Lyles (0-1) allowed two runs (one earned) on five hits and a walk with six strikeouts in five innings. Pham's homer came on the penultimate batter he faced.

Franchy Cordero had three of the Padres' five hits.

--Field Level Media