Austin Hedges singled home the go-ahead run in a two-run seventh inning, as the San Diego Padres nicked the Phillies, 2-1, on Saturday afternoon.
An RBI triple by Carlos Asuaje preceded the hit by Hedges and tied the game.
The Padres won for the fifth time in six games.
Maikel Franco hit his 13th homer for the Phillies, who have dropped five straight. They also fell to 11-23 in one-run games.
Aaron Nola (6-6) saw a personal three-game winning streak end, despite allowing two runs on four hits over eight innings. He struck out nine and walked two.
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Jhoulys Chacin (8-7) earned the victory for the Padres.
Starting pitching report
Nola cruised through the first six innings, extending his scoreless-innings streak to 17. But with the Phillies up 1-0, Hunter Renfroe, leading off the seventh, slapped an excuse-me double just inside the first-base line.
Two outs later Asuaje smoked Nola's 2-1 fastball off the center-field fence for his RBI triple, and Hedges followed by lining an 0-2 fastball into right, scoring Asuaje.
Nola nonetheless became the first Phillies pitcher since Jerad Eickhoff in 2015 to work seven or more innings and allow two runs or fewer in four straight starts.
Chacin was 2-5 with a 9.08 ERA in his first eight road starts of the season, but he allowed one run on three hits over 6 1/3 innings, while striking out six and walking two.
Luis Garcia worked a scoreless inning in relief of Nola.
Padres reliever Kirby Yates entered the game in the seventh with runners on second and third and one out and retired Franco on a pop to short and Andrew Knapp on a flyout to left.
Ryan Buchter blanked the Phils in the eighth, and Brandon Mauer worked a scoreless ninth to earn his 19th save.
At the plate
Franco offset his solo homer in the fifth by grounding into his 17th double play of the season. He already led the majors in that category.
Joseph singled, doubled and walked, and has reached base seven times in the first two games of this three-game series.
The Padres managed three of their five hits in the pivotal seventh inning.
RHP Jerad Eickhoff, who has been idled by an upper back strain, makes his first start since June 17 when the Phillies play their last game before the All-Star break Sunday. Eickhoff (0-7) is also seeking his first victory in 17 starts. That dates back to Sept. 21, 2016, when he beat the Chicago White Sox.
He will be opposed by RHP Trevor Cahill (3-2, 2.96).