PHILADELPHIA » If the Arizona Diamondbacks end up playing Philadelphia in the postseason, they won’t be discouraged about losing their last series.

After all, they did beat Roy Halladay and they split six meetings.

John Mayberry Jr. hit a two-run homer, David Herndon tossed three scoreless innings in relief and the Phillies beat the Diamondbacks 4-1 Thursday night in a matchup of division leaders.

The major league-leading Phillies took two of three in a potential playoff preview, improving to 14-1-1 in their last 16 series.

“We’ve got a long way to go,” shortstop Willie Bloomquist said. “To be the best, you’ve got to beat the best. We did beat Halladay, so that’s a positive.”

A thunderstorm delayed the game for 2 hours, 17 minutes after three innings. Neither starting pitcher returned when play resumed.

Herndon (1-2) gave up one hit and struck out four to earn his second career win. Ryan Madson finished for his 23rd save in 24 tries.

“They just pounded the zone, all of them,” Diamondbacks manager Kirk Gibson said. “They did a good job shutting us down.”

Ian Kennedy (15-4) gave up three runs and five hits in three innings, failing to become the NL’s first 16-game winner. He had won his previous seven starts.

Arizona remained 21⁄2 games ahead of the defending World Series champion San Francisco Giants in the West.

Phillies starter Vance Worley allowed one hit in three scoreless innings. The rookie remained 8-1, but Philadelphia has won his last 11 starts.

Paul Goldschmidt homered for the Diamondbacks. The rookie has four homers in 47 at-bats since getting called up on Aug. 1.

“Goldschmidt and (Lyle) Overbay were our offense in the series,” Gibson said.

The Phillies, who lead Atlanta by 81⁄2 games in the East, are a season-best 38 games over .500 and have reached 80 wins in the second-fastest time in franchise history. They did it in 121 games in 1976.

Wilson Valdez, who hit a tie-breaking two-run double in Wednesday’s 9-2 win, put the Phillies up 1-0 with an opposite-field RBI double in the second. Raul Ibanez hit a one-out double and scored on Valdez’s liner to right.

The Phillies played without St. Anthony alumnus Shane Victorino, who had his suspension for his part in a benches-clearing brawl at San Francisco on Aug. 5, reduced to two games. He will not play tonight against Washington.