MIAMI -- Chris Johnson culminated the Miami Marlins' productive line of base hits and an improbable victory.

Johnson' walk-off RBI double in the bottom of the ninth inning lifted the Marlins to a 7-6 win over the San Diego Padres on Friday night.

Facing San Diego closer Brandon Maurer, Johnson hit a shot that bounced over the wall in right field and scored Jeff Francoeur from second for the winning run.

"When I hit it I put my head down, I didn't get it all of it and when I was running I kind of saw where they were playing -- a little bit more shallow, obviously to try to throw somebody out at the plate," Johnson said. "I was just hoping it would carry enough to get over his head. The center fielder almost got there. I'm just glad he didn't."

For Johnson, the hit also helped overcome reduced playing time lately. The Marlins added Xavier Scruggs, a second right-handed first baseman, last week. Scruggs joined Miami from Triple-A New Orleans on Aug. 19, started Friday night.

Johnson replaced Scruggs in a double switch in the fourth inning. After going hitless in his first three at bats, Johnson delivered at a crucial time.

"I'm here to get my work in; I'm not going to pout about who's out there," Johnson said. "As long as we win ball games and get us where we want to go that's what everybody should be happy about."

Fernando Rodney (2-3) pitched a perfect ninth for the win.

The Marlins erased a 6-2 deficit with a three-run eighth and a run in the seventh.

Martin Prado's two-run single with the bases loaded off Maurer (0-4) in the eighth put Miami within 6-5. Christian Yelich then drove Maurer's 1-2 pitch to center field for a single that scored J.T. Realmuto with the tying run. Maurer entered with two outs in the inning after Miami loaded the bases against reliever Brad Hand.

"We just kept tacking on," Miami manager Don Mattingly said. "They were all huge hits."

Francoeur went 3-for-4 and walked once in his first start with the Marlins. Francoeur was acquired from the Atlanta Braves in a three-team trade on Wednesday.

Facing the team that traded him in a seven-player deal on July 29, San Diego starter Jarred Cosart pitched five innings, allowing two runs and five hits. Cosart also struck out three in his fifth start with the Padres but had to leave because of a blister in the middle finger of his throwing hand.

"I thought he was outstanding," Padres manager Andy Green said. "We would have liked to run him seven innings but the blister kind of came up on him."

San Diego erased a two-run deficit after a four-run fourth against Miami starter David Phelps. Luis Sardinas keyed the rally with a bases-loaded double as the Padres chased Phelps, who allowed four runs and two hits and struck out six in 3 2/3 innings.

Sardinas increased the Padres' lead with his first home run of the season in the sixth. Sardinas drove Marlins reliever Mike Dunn's pitch over the wall in left field for a 6-2 San Diego advantage.

Marcell Ozuna's single in the seventh off San Diego reliever Jose Dominguez began the Marlins' comeback.

The Padres erased a two-run deficit on Sardinas' bases-loaded double in the fourth for a 3-2 lead. Sardinas' drove Phelps' pitch deep to right center, scoring Alex Dickerson, Ryan Schimpf and Patrick Kivlehan. Sardinas raced home from second when Phelps failed to field Cosart's grounder down the first base line and beat first baseman Xavier Scruggs' throw.

"It was gratifying what I did, but at the end of the day it's about the team," Sardinas said of his two-hit, four-RBI-performance. "Unfortunately we couldn't get the win."

Schimpf increased San Diego's lead to 5-2 with his home run in the fifth. Schimpf drove Miami reliever Nick Wittgren's pitch over the wall in right center for his 15th homer of the season.

The Marlins struck quickly on Ozuna's RBI double that scored Yelich in the first. Ozuna drilled a ball past Kivlehan in right to give Miami a 1-0 lead.

Yelich increased Miami's lead to 2-0 in the third when his groundout drove in Realmuto, who reached on Schimpf's fielding error at second and advanced to third after Prado's single to right.

NOTES: Marlins manager Don Mattingly removed OF Ichiro Suzuki from the starting lineup for the series opener against San Diego, saying Suzuki, 42, needed a break. Suzuki has started 10 of Miami's 11 games since OF Giancarlo Stanton sustained a groin injury on Aug. 13 and hit .171 during the stretch. ... Stanton, who suffered a Grade 3 left groin sprain, told the media before Thursday's game against Kansas City that he will try to return to the lineup before the end of the regular season. .... Padres RHP Tyson Ross made his first appearance since April in a rehabilitation start at Class A Lake Elsinore on Thursday. Ross was San Diego's opening day starter April 4 but experienced shoulder inflammation before his second scheduled start. ... The Padres placed RHP Brandon Morrow on paternity leave and recalled LHP Buddy Baumann from Triple-A El Paso. Baumann, 28, was previously twice recalled by the Padres this season.