SAN DIEGO -- Miami catcher Jeff Mathis capped a five-run first with the third grand slam of his career and right-handed starter Tom Koehler allowed two runs over six innings Tuesday as the Marlins defeated the San Diego Padres 5-2 at Petco Park.

Koehler (5-6) gave up six hits and a walk while striking out eight. Right-handed closer A.J. Ramos picked up his 20th save.

Left-hander Drew Pomeranz (5-7), who gave up all five Marlins runs in the first, took the loss. The Padres have lost four straight.

After the first, Pomeranz and relievers Carlos Villanueva and Kevin Quackenbush blanked Miami on three hits over eight innings.

The Marlins jumped on Pomeranz in a top of the first that took almost a half-hour to complete as both managers conferred with the umpiring crew. Miami's Don Mattingly played the game under protest after arguing a controversial play at first for nearly seven minutes.

The game opened with the Padres left-hander walking Adeiny Hechavarria ahead of a broken-bat single by Martin Prado.

Christian Yelich followed with a roller up the first-base line that was fielded by Wil Myers. As the Padres first baseman went to tag Yelich, he attempted to dive around Myers but was called out by first base umpire Cory Blaser.

Mattingly came out to argue that Yelich was safe. Even after the umpires conferred twice and didn't change the call, Mattingly asked for a video appeal. As the call was being upheld, Padres manager Andy Green came onto the field to discuss the situation.

When play finally resumed, Pomeranz walked Marcell Ozuna on four pitches to load the bases ahead of striking out Giancarlo Stanton for the second out.

Chris Johnson then hit a sharp grounder to the right of Padres shortstop Alexei Ramirez, who made the stop in the hole but had no play as Hechavarria scored the first run.

Mathis followed with his first home run of the season -- and his first grand slam since he victimized the Padres on June 30, 2013.

Pomeranz retired 13 of the last 18 Marlins he faced. But the damage had been done. He gave up five runs, five hits and five walks with six strikeouts in five innings.

The Padres scored single runs off Koehler in the second and fourth with Alexi Amarista supplying two RBI singles with two outs.

In the second, third baseman Ryan Schimpf, who was promoted from Triple-A El Paso earlier in the day, doubled in his first major league at-bat, reached third on a groundout and scored on Amarista's single.

In the fourth, Christian Bethancourt doubled with two outs and scored on Amarista's single.

NOTES: The Padres promoted INF Ryan Schimpf from Triple-A El Paso and designated C Hector Sanchez for assignment. Schimpf was hitting .355 with 15 homers and 48 RBIs in 51 games for the Chihuahuas with a .432 on-base percentage. He ranked second in the Pacific Coast League in homers. ... Padres RHP Tyson Ross, who has not pitched since opening day because of right shoulder inflammation, played catch from 150 feet on Tuesday and could have a bullpen session by the weekend ... Padres OF Travis Jankowski, who departed Monday's game with what looked to be a serious ankle sprain, was running Tuesday. ... RF Giancarlo Stanton returned to the Marlins' starting lineup, meaning Ichiro Suzuki will have to wait at least one more day before getting his 4,256th professional hit to equal Pete Rose's career total.