Ahmed's homer, his third of the season, made it a 3-0 lead and Corbin's two-out single drove in the final run of the inning as the Diamondbacks (15-6) tied a franchise record for the best 21-game start to a season. Arizona is the first team since the 2003 San Francisco Giants to win its first seven series.

Christian Villanueva broke up Corbin's shutout with a two-run homer in the sixth inning as the Padres (8-15) lost for the fifth time in six games.

Corbin (4-0) gave up two hits and two runs in six innings, with 11 strikeouts and one walk. He joined Washington's Max Scherzer, the Yankees' Luis Severino and Boston's Rick Porcello as the only four-game winners in MLB.

In his last three home starts, Corbin has given up four hits and two runs in 22 1/3 innings while striking out 31. He took a no-hitter into the eighth inning of his Tuesday start against the Giants before losing it on a two-out, check-swing single. His ERA is 1.89.

Archie Bradley got the final four outs for his second save, pitching around a one-out double by Villanueva in the ninth inning.

Villanueva's homer, his seventh, came after Wil Myers struck out on a pitch in the dirt but made it to first on a wild pitch. Since his major league debut last Sept. 17, Villanueva has 11 homers in 104 plate appearances.

Rookie Joey Lucchesi (2-1) gave up five hits and four runs, with four walks and four strikeouts. He had given up only one earned run combined in his previous three starts over 17 innings.

Paul Goldschmidt, who had two of Arizona's six hits, walked to open the fourth inning before A.J. Pollock singled to right field. Goldschmidt took third on a fly ball to center and scored on Lucchesi's errant pickoff throw to first after Pollock broke for second.

Ahmed hit the next pitch for his third homer of the season for a 3-0 lead, and Corbin singled in the fourth run of the inning after Deven Marrero walked and stole second.

--Field Level Media