Fried pitched 6 1/3 shutout innings, lowering his ERA to 1.24. Duvall broke a tie by golfing his 100th career homer, which caromed off the left-field pole with one out in the ninth.
"With the skid we had going, it was good to scrape that out," Duvall said. "I'd like to start hitting them a little bit straighter. That was like a 9-iron draw. I just caught enough there."
"It's a great moment, but we didn't win the game," Harrison said, "so it doesn't really mean much to me right now."
The Braves regained the lead when Duvall lunged at an outside pitch from Brandon Kintzler (1-1) and pulled it down the line.
Fried, who allowed four hits and struck out seven, again pitched like an ace for the injury-plagued Braves.
"He's like all good pitchers -- they have a plan for every ball they throw," manager Brian Snitker said. "I feel so good with him on the mound. It's fun to watch. He has a chance to be really good for a long time."
The left-hander allowed at least one runner in each of the first three innings, but then had a stretch where he struck out six of seven batters.
"I just wanted to go out there and keep it simple, eat as many innings as I could and hopefully start a nice little winning streak," Fried said.
The Braves' other starters are 0-8, but thanks to Fried, Atlanta trails Miami by only one game in the NL East.
"We've obviously been unfortunate with some injuries," Fried said. "Hopefully we can hang in this thing and weather the storm. When they come back, we should be able to get on the right foot."
Smith (1-0) worked the eighth. Mark Melancon pitched around a two-out single in the ninth for his fourth save to complete a six-hitter.
Miami went 0 for 5 with runners in scoring position.
This weekend's celebration of the Negro Leagues stirred a memory for Marlins manager Don Mattingly, who said he was playing at Single-A Greensboro in 1980 when he happened to meet the legendary pitcher Satchel Paige.
"I was in the South Atlantic League in a Shoney's, just going in there after a game to get a burger, and Satchel was sitting there all by himself," Mattingly said. "We ran back and got a couple of balls, and I still to this day have a Satchel Paige baseball."
Marlins: OF Corey Dickerson went on the bereavement list, and INF Lewin Diaz was recalled from the alternate training site. Dickerson is expected back early next week. Diaz singled as a pinch hitter in the ninth in his first major league at-bat.
Braves: LHP Robbie Erlin (0-0, 9.00) will make his first start of the season in the rubber game of the series Sunday, and his second since 2018. The Braves are hoping he can throw 65 to 70 pitches, Snitker said.
Marlins: RHP Elieser Hernandez (0-0, 2.79) will make his third start of the year.
More AP MLB: https://apnews.com/MLB and https://twitter.com/AP-Sports
Follow Steven Wine on Twitter: https://twitter.com/Steve-Wine
Acuña, Olson power Braves to doubleheader sweep of Marlins
— Ronald Acuña homered on the first pitch of the game, Matt Olson hit his 24th homer and the Atlanta Braves beat the Miami Marlins 6-2 to sweep their doubleheader Saturday.
Day after losing Tatis to ban, Padres lose to Nationals 4-3
— San Diego and new slugger Juan Soto repeatedly failed to come through in the clutch against his former...
Seager 26th HR matches career high as Rangers beat M's 7-4
— Corey Seager matched a career high with his 26th homer and rookie Bubba Thompson drove in a run with a sacrifice squeeze bunt as the Texas Rangers overcame an early deficit to beat the Seattle Mariners 7-4 on Saturday night.
Kiner-Falefa's bunt wins it for Yankees
The Yankees go ahead in the ninth thanks to a bunt single from Isiah Kiner-Falefa.
Hernandez, Meneses tag Darvish for back-to-back jacks
The Nationals tie it up as Yu Darvish surrenders back-to-back home runs to Yadiel Hernandez and Joey Meneses.
Kiner-Falefa helps Yankees squeeze past Red Sox 3-2
— Isiah Kiner-Falefa drove in the go-ahead run with a safety squeeze in the ninth inning and hit his first career homer with New York, sending the AL East-leading Yankees past the Red Sox 3-2 on Saturday night for just their second win in 10 games.