MIAMI -- Maybe manager Mike Redmond wasn't the Marlins' problem.
Jennings gave up his job as general manager to move into the dugout and replace Redmond, who was fired Sunday. The Marlins lost their fourth game in a row and seventh in eight games, but Jennings tried to put a positive spin on the latest defeat.
"There's a lot of good to take away," he said. "There's a great energy in the clubhouse and dugout. We just came up a little short."
The Marlins totaled six hits, the last of which was rookie J.T. Realmuto's first career homer, a two-run shot with none out in the seventh. The lack of offense had Jennings working overtime on his first day as a manager.
"It was surreal to be there in the moment," he said. "It definitely moves quicker in the dugout than it does in the suite upstairs."
Like Miami, Arizona had been scuffling until David Peralta hit a two-out RBI double in the 13th inning off Cishek (1-4). The Diamondbacks broke a four-game losing streak.
"I needed that," manager Chip Hale said. "We all needed that."
Rubby De La Rosa pitched a career-high nine innings for the Diamondbacks and allowed two runs. In 35 previous career starts, the right-hander had never gone more than seven innings.
"A great start from Rubby," Hale said. "What great stuff."
Chris Owings singled to start the 13th, stole second and went to third on a groundout. Peralta then pulled a double against Cishek.
"I faced him last year and know what kind of pitches he's got," Peralta said. "He just hung a slider, and I was able to swing the bat and get it to the line."
Cishek, who has an ERA of 8.22, gave up three hits in two innings.
"It's just really unexplainable," he said. "I felt like I was throwing the best I've thrown all year."
Yasmany Tomas had a two-run double in the fourth for Arizona's other runs.
Addison Reed (1-2) pitched around two walks in the 12th inning. Diamondbacks rookie Enrique Burgos issued a walk in the 13th and Ichiro Suzuki stole second, but the call was reversed by a replay review, erasing the runner.
Burgos then struck out Jeff Baker for his first career save.
Miami's Dan Haren allowed two runs in eight innings, his longest outing this season. For the fourth start in a row, Haren didn't issue a walk.
Moments before the game, Suzuki put a Marlins dress tie around Jennings' neck and everyone in the dugout shared a good laugh.
"It was almost a feeling of acceptance," Jennings said. "That was a special moment coming from a Hall of Famer. It made me feel like part of the group."
The Marlins had little to smile about after that, as their offensive slump continued. They came within an out of being no-hit Sunday when they were shut out by Atlanta's Shelby Miller, but Jennings counted 12 hard-hit balls Monday.
"This is a good hitting ballclub," he said. "Tonight wasn't our night."
Miami was without cleanup hitter Marcell Ozuna, who left shortly before batting practice because of a personal issue. He'll be back Tuesday, Jennings said.
Miami's Dee Gordon, who leads the majors in batting, went 0-for-5 to drop his average to .406.
Marlins: RHP Jarred Cosart was placed on the 15-day disabled list, retroactive to Thursday, with vertigo. Cosart has been battling an inner-ear infection and is on medication. ... RHP Mat Latos is still nursing a bruised left shin but is expected to be able to make his next scheduled start Thursday, Jennings said.
Diamondbacks: LHP Patrick Corbin (elbow) allowed three runs over five innings in an extended spring training game. RHP Matt Stites (elbow) pitched one scoreless inning. INF Jake Lamb (foot) went 2-for-4.