Miami's Opening Day starter, Volquez was 0-7 before collecting his first Marlins victory in his 10th start. It also snapped a dry spell of 16 starts between wins, dating back to Aug. 25, 2016, when Volquez beat Miami with the Royals.
"For me, I'm 1-0. I can't keep thinking about 0-7," Volquez said. "As a pitcher, you have to have a strong mind and stay positive to pitch every fifth day. Don't think about numbers. I've been pitching a little bit better lately. I think I'm going to get some wins."
Volquez scattered three hits, and had a stretch of retiring 13 straight.
"He made pitches on us," Phillies catcher Cameron Rupp said. "I can't recall us swinging at too many bad pitches. We just haven't been hitting the ball. There's just no other way to put it."
The Marlins have won back-to-back games for the first time since April 22-23 at San Diego. They also found a way to beat their nemesis, Jeremy Hellickson, who was 4-2 with a 2.61 ERA in his career against them. The Phillies right-hander gave up four runs in six innings.
"Hellickson has been a tough guy on the mound for us," Dietrich said. "We wanted to come up with a new approach, a plan. As a team, as a unit, we went with something a little bit different. It seemed to work. We didn't by any means crush him, but we did enough to win the ballgame. That's all that matters."
Dee Gordon sparked a two-run third inning with an RBI double, and he was driven in by Giancarlo Stanton. Stanton, who entered the game hitting .368 against changeups, grounded a single to center off a 81.9-mph changeup from Hellickson.
Dietrich's homer came in the sixth, after the Phillies pulled within a run through Aaron Altherr's RBI single in the top of the inning.
"We had some opportunities," Phillies manager Pete Mackanin said. "We didn't do enough offensively again. We only had four hits again."
MOMENTS THAT MATTERED Two-out single, towering homer: After the Phillies chipped back to 2-1 in the sixth, Hellickson was primed for a shutdown frame, retiring Marcell Ozuna and Justin Bour. But J.T. Realmuto kept the inning alive with a single to set up Dietrich's towering two-run homer to right, padding the lead to three. Per Statcast™, the home run traveled a projected 360 feet with an exit velocity of 98.1 mph. The question was if it had the distance, because it clearly had the height. With a launch angle of 33 degrees, the ball was as high as 126 feet before clearing the wall.
"For me, Hellickson is a guy who can throw four or five pitches for strikes," Dietrich said. "He's constantly changing speeds.You have to be ready to hit any pitch in any count. Really, it's about seeing the ball as deep [into the strike zone] as possible. Letting it get to you and putting a good swing on it. That's kind of what I did."
Change-of-pace strikeout: Volquez saved his most significant pitch of the night for his last. On his 87th and final offering, the right-hander fanned Tommy Joseph swinging through an 83.6-mph changeup. The strikeout stranded Cesar Hernandez at third in a 2-1 game. Volquez received a big boost in the inning with runners at the corners and one out, when Realmuto threw Altherr out trying to steal second.
"It was a close play, but we've got to do something to make things happen on offense," Mackanin said of Altherr's attempted steal.
"Obviously, it's been an awful month until this point. It's been a long time. But, at this point, you've got to move forward. Hopefully, we've started to creep up with some momentum. We're playing better. We're getting a little better pitching. Everything seems to be a little better." -- Marlins manager Don Mattingly, on back-to-back wins for first time in more than a month
"They talk about hitting being contagious; so is losing. I've just got to make sure we don't get complacent with losing. We don't get used to losing. That's my challenge." -- Mackanin, on the Phillies having won six games in May
A pivotal review call came up in the Marlins' favor in the sixth inning, after the Phillies challenged if Joseph's foul ball to right field actually deflected off Stanton's glove in fair territory. With runners at the corners and Miami leading, 2-1, Stanton gave chase down the right-field line, making a sliding attempt at the catch. The ball deflected off his glove and the umpires immediately ruled it a foul ball. After a review of one-minute, 20-seconds the decision was the call stands.
"The foul ball was huge," Mattingly said. "That ball was barely foul. Now, I'm glad he didn't catch it. We get out of the inning still with the lead."
WHAT'S NEXT Phillies:Vince Velasquez gets the call Tuesday for the Phillies in the middle game of a three-game set with the Marlins at 7:10 p.m. ET. The right-hander will be looking for his first win since May 1 at the Cubs. In his last outing he went five innings and gave up just one run to Colorado, striking out seven.
Marlins:Justin Nicolino (0-1, 5.40 ERA) will make his third start since being promoted from Triple-A New Orleans. This will be his first outing since May 19 at the Dodgers.