SAN DIEGO -- Joe Dunand had some news to share Saturday. His uncle, Alex Rodriguez, was on the list of people to call when he got word of his promotion to the big leagues.

"Get after it,” Rodriguez told his nephew. “It's the same game you've played your whole life, so just go out there and do what you do."

Dunand did just that Saturday night in an 8-0 victory over the Padres at Petco Park, becoming the third Marlin to homer in his first Major League at-bat. It helped snap a six-game skid for Miami, which scored just 21 runs during that stretch.

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“Honestly, I've been saying I blacked out, I think,” said Dunand, who received the ball in exchange for the fan meeting teammate Jazz Chisholm Jr. “I don't really remember much. I just remember my game plan: I was looking for the ball up and hit it hard up the middle. I think I picked back up rounding around second. It was a great feeling.”

Dunand pulled southpaw Sean Manaea’s changeup on the outside corner into the first row in left-center to give Miami a 1-0 lead in the third inning, joining Jeremy Hermida and Mitch Lyden as the only players in franchise history to go deep in their first ABs.

Rodriguez, who debuted 14 months before Dunand was born, finished his 22-year career with 696 homers. An 18-year-old A-Rod didn’t collect his first MLB hit until his fifth career at-bat in 1994. His first homer didn’t come until his 34th game, on June 12, 1995.

In his second at-bat, Dunand added a double as part of a fifth-inning rally. Southern California native Garrett Cooper, who had family in attendance, delivered a two-out, two-run double to make it a 3-0 ballgame. It was more than enough for right-hander Pablo López, who went eight innings to match his career high.

“I think he's taking after his uncle,” Cooper said of Dunand. “That's a big first AB. I remember my first AB, and I didn't do that. Good for him. That's a memory he'll always have, off a good All-Star pitcher. And to come up with a double after that's huge for him. It was a huge start for us to get that first run to take the lead early. Can't say enough about the job he did in his first game.”

A second-round selection out of North Carolina State University in the 2017 MLB Draft, Dunand was part of the Marlins’ taxi squad on their seven-game road trip to San Diego and Arizona. He had been taking batting practice and fielding grounders with the club, so he wasn’t too concerned about falling out of rhythm despite last appearing in a game on Tuesday for Triple-A Jacksonville.

With utility player Jon Berti headed to the injured list for an undisclosed reason on Saturday -- a day after the same thing happened to third baseman/outfielder Brian Anderson -- Miami selected Dunand’s contract from Jacksonville. Primarily a third baseman, Dunand provides versatility, with time at first base and shortstop.

Because of such short notice, Dunand’s family in Miami couldn’t be in attendance in San Diego. It was a moment the graduate of Miami’s Gulliver Preparatory Academy had been preparing for his whole life.

Dunand has a slash line of .236/.309/.367 in 348 games across five Minor League seasons. In 14 games for the Jumbo Shrimp this season, he posted a .794 OPS. Last year epitomized the ups and downs of his professional career.

Following a strong showing in the Dominican Winter League, where he compiled a .939 OPS for Escogido in 21 games, he went 7-for-28 with five runs, two doubles, two homers (including a walk-off shot on March 17) and seven RBIs in Grapefruit League play. But he didn’t make the Opening Day roster, then was limited to 69 Minor League games due to a UCL fracture in his left thumb.

“This is just a dream come true,” Dunand said. “This is everything you dream about. Just coming here and being able to play at the highest level and perform at a high level and help the team win, which is the most important thing, it's a great feeling.”

Through it all, Dunand has absorbed the encyclopedia's worth of knowledge from his uncle, whom he called one of the smartest people he has known. 

“I think everybody's happy for him, that's the biggest thing. And then he obviously plays well,” manager Don Mattingly said. “Caught the ball all day long, didn't look like he was one bit nervous. But I think when you have a young guy come up, it just reminds you of when you started and the first time you played. Everybody would like to hit a homer that first at-bat.”