ATLANTA -- Earlier in the season, the Marlins got a glimpse of rookie Merandy Gonzalez as a reliever. On Monday night, the organization gave the 22-year-old the opportunity to make his first big league start.
The right-hander showed plenty of potential, but also gave reminders that he is far from a finished product. Gonzalez gave up three runs in 4 2/3 innings, including a leadoff homer to Ronald Acuna Jr., in the Marlins' 6-1 loss to the Braves at SunTrust Park.
Acuna belted leadoff homers in both games of the doubleheader, becoming the first player to do so since Brady Anderson of the Orioles on Aug. 21, 1999, against the White Sox.

"Acuna got us again early," Marlins manager Don Mattingly said. "That always puts you back on your heels a little bit. After that, it seemed like [Gonzalez] settled down a little bit, and got some easier outs, and hung in there."
Overall, it was a rough day for the Marlins, as they were swept in the two games, and now have lost three straight, and 12 of their last 14.
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Gonzalez was called up from Double-A Jacksonville as Miami's 26th man for the twin bill, and he will return to the Jumbo Shrimp. Groomed to be a starter, the right-hander has thrown seven relief appearances for the Marlins, but he's spent most of the season at Double-A.
"This experience, like all the experiences, you've got to take the good and bad with it," Gonzalez said through an interpreter. "I've learned more about the strike zone in the Majors and also about executing pitches. It's not all about executing pitches. It's not just executing, sometimes they get the best of it. You just keep going."

The Marlins acquired Gonzalez in July 2017 from the Mets as part of the AJ Ramos trade. The rookie is part of the team's long-term plans and likely will be a September callup.
"He seems to be a guy who is fairly calm," Mattingly said. "You don't see him overly excited, or fidgety out there. He's pretty much quiet and under control. He's got some weapons. He's got a breaking ball, a changeup. He's going to need to get the ball to both sides of the plate, like everyone else. But he's a different mix than our other guys. Right now, we're trying to find out what he is and keep developing him, and let him blossom into what he's going to be."
Miami didn't give Gonzalez much support, scoring one run off Mike Foltynewicz. That came in the sixth inning on Starlin Castro's RBI double.
Freddie Freeman added a home run off Tayron Guerrero in the seventh inning. The blast came on a slider. In the inning, Guerrero's fastball maxed at 104 mph. It was the 11th time this season a pitcher reached that mark.
The doubleheader was doubly painful for the Marlins, because in both games their starting third baseman exited due to injury. In the second inning of the nightcap, Miguel Rojas limped off the field after getting thrown out trying to go from first to third on John Holaday's two-out single. Rojas hurt his left ankle on the play and was replaced by Yadiel Rivera.

In their 9-1 loss in Game 1, Martin Prado suffered a left quad strain and was placed on the 10-day disabled list.
Rojas noted he saw Acuna on his heels, so he gambled trying to take the extra base.
"I saw he was flat-footed, and I was trying keep going there, to make it to third," Rojas said. "But I was aware of the situation. It wasn't the right time to try to take the extra base. The pitcher was behind. It was two outs, early in the game. It's on me."
MOMENTS THAT MATTERED
The Marlins managed just one run in each game, and Castro's double in the sixth inning came after J.T. Realmuto walked. At the time, Miami trailed, 3-1, and had a chance to chip back closer. But Brian Anderson lifted a fly ball to right field, and JT Riddle grounded to second, ending the inning.
The lineup has been hurt without Prado and Rojas available, but Mattingly noted the team has been in a collective slump for a while.
"Really hard to explain," Mattingly said. "We had gotten rolling there for a little bit, where the offense seems to be clicking. We hit this little stretch where it seems to be going in the other direction. Obviously, you've got to give their [starters] credit, both guys. They've got really good stuff. But that's every day. That's coming every day."

SOUND SMART
Gonzalez became the 12th different Marlins starter this season, which is tied for most in the National League. The 22-year-old also is the sixth different Miami pitcher to make his first career big league start.
YOU GOTTA SEE THIS
Guerrero took his fastball up to another level in the seventh inning. The 6-foot-8 right-hander threw 13 four-seam fastballs that averaged 101.9 mph. But the one that caught the attention of Statcast™ most was the 104-mph heater that Markakis fouled off. It's just the 11th time this year Statcast™ has tracked a pitch as high as 104 mph. The other 10 were by either Jordan Hicks of the Cardinals or Yankees closer Albertin Chapman.

HE SAID IT
"I think we have to bring a little more energy because it seems to me we're a little too comfortable with losing games and not doing anything about it. Mentally, we're just coming in and coming out of the clubhouse. I think it's something we have to address in the next few days where guys just have to take a little more pride because this is the big leagues, and for me, it took a long time to get to the big leagues. So this is something I take really seriously. Hopefully, this young group of kids understands how fortunate they are to play in the big leagues. I think the next few days they're going to hear from me because this is not acceptable." -- Prado, on the state of where the team is right now
UP NEXT
Rookie right-hander Trevor Richards, arguably the Marlins' most consistent starter, takes the mound on Tuesday against the Braves at 7:35 p.m. ET at SunTrust Park. Richards' changeup is his best pitch. He's induced 117 swinging strikes on the pitch, third most of any pitcher in the Majors. Anibal Sanchez starts for the Braves.