Manny Machado homered and Jackson Merrill knocked in three runs as the San Diego Padres tuned up for the National League playoffs with a 12-4 rout of the visiting Arizona Diamondbacks on Sunday.

J.P. Sears (9-11) twirled 5 2/3 innings and threw a season-high 113 pitches for the win, allowing two runs on seven hits and three walks to go with four strikeouts. San Diego (90-72) boasts back-to-back 90-win seasons for the first time.

Brandon Pfaadt (13-9) was rocked for eight runs (seven earned) on six hits in four-plus innings, walking none and fanning five. Arizona (80-82) lost its last five games after being within one game of the final wild-card spot entering Wednesday's play.

Ketel Marte led off the game with a homer, his 28th of the year, but few highlights followed for the Diamondbacks. The Padres responded with five straight hits to open the bottom of the first on Pfaadt's first 10 pitches.

Singles by Fernando Tatis Jr., Ryan O'Hearn and Machado tied the game. Merrill doubled to right for a run and Xander Bogaerts lined a two-run double to left, then scored two batters later on Jake Cronenworth's sacrifice fly.

Arizona got a run back in its half of the third on Tim Tawa's double-play ball to third, but Machado led off San Diego's half of the inning with his 27th homer of the year to left.

The Padres broke it open in the fifth with three more runs off Pfaadt and reliever Philip Abner. Merrill laced a two-run double to right-center with the bases loaded and Gavin Sheets brought in the other run on a fielder's choice.

San Diego collected three more runs with two outs in the seventh. Cronenworth looped an RBI single to left-center and Jose Iglesias slashed a two-run double down the left field line.

O'Hearn, Machado and Merrill each collected two of the Padres' 11 hits. They open the playoffs on Tuesday when they begin a best-of-three series at the Chicago Cubs. The teams met six times in the first three weeks of the season. Not only did the Cubs and Padres each win three games, they each scored 25 runs.

Arizona scored twice in the ninth on a one-out error by O'Hearn at first. Geraldo Perdomo was credited with an RBI on the play, giving him a career-high 100 for the year.