Luis Arraez went 3-for-5 with two doubles, a triple, a run and an RBI to help the San Diego Padres post a 5-3 victory over the Arizona Diamondbacks on Friday night in the opener of a pivotal three-game series at Phoenix.

Jackson Merrill and David Peralta each had two hits and one RBI as San Diego clinched the top wild-card spot and No. 4 seed in the National League playoffs. The Padres (92-68) will host a yet-to-be determined opponent beginning on Tuesday.

Arizona (88-72) lost for the fourth time in five games and is part of a three-way virtual tie for the other two wild-card spots with the Atlanta Braves (87-71) and the New York Mets (87-71).

Arraez increased his average to .314 as he attempts to hold off the Los Angeles Dodgers’ Shohei Ohtani for the NL batting title. Ohtani has a .309 average to go along with his league-leading totals in homers (54) and RBIs (130).

Corbin Carroll homered and Eugenio Suarez had two hits for the Diamondbacks.

San Diego’s Yu Darvish (7-3) gave up three runs and three hits over 5 1/3 innings. He struck out four and walked three.

Robert Suarez worked around a one-out walk in the ninth for his 36th save.

Arizona’s Merrill Kelly (5-1) allowed five runs and eight hits over 5 2/3 innings. He fanned eight and walked one.

Kelly was 9-3 in 15 career starts against the Padres entering the contest but was quickly roughed up for four runs and four hits in the first inning.

Manny Machado and Merrill had RBI singles before Xander Bogaerts followed with a grounder in which Merrill was forced out at second, but second baseman Ketel Marte’s throw to first was wild and allowed Machado to score.

Two batters later, Peralta stroked an RBI single to cap the outburst.

In the bottom of the first, Carroll hit a leadoff homer. Later in the inning, Lourdes Gurriel Jr.’s sacrifice fly pulled Arizona within 4-2.

San Diego added a run in the fourth when Kyle Higashioka singled with two outs and scored on Arraez’s triple.

Arizona got the run back in the sixth on Eugenio Suarez’s two-out RBI single.

–Field Level Media