BOSTON (AP) — Vaughn Grissom was rounding third when it sank in.

He had just cleared the Green Monster for his first big league hit, and he gave himself an emphatic clap before finishing his home run trot.

“That was like a ‘We made it’ moment, I guess,” the Braves’ top prospect said after homering in his major league debut to help Atlanta beat the Boston Red Sox 8-4 on Wednesday. “Like a ‘We did it’ type of feeling.”

Grissom homered onto Lansdowne Street and then singled and scored another run, and Marcell Ozuna hit a three-run homer to help Atlanta complete a two-game sweep. Kyle Wright earned his league-leading 14th win for the defending World Series champions, who arrived in Boston after losing four of five to the first-place Mets and are now seven games back in the NL East.

The Braves had Thursday off and begin a four-game series at Miami on Friday night. That is followed by four more games at home with the Mets next week.

“We had a rough weekend,” Braves manager Brian Snitker said. “Which is fine; it’s going to happen. I did not think this was going to be bump free.”

Called up earlier in the day from Double-A Mississippi, the 21-year-old Grissom went hitless in his first two at-bats but hit the first pitch he saw in the seventh inning completely out of Fenway Park. He tossed his bat aside before taking off around the bases, clapped his hands as he rounded third and arrived home to be congratulated by Michael Harris II, who had singled ahead of him.

Harris, another young Braves star, was also called up straight from Double-A in May. The 21-year-old entered Wednesday’s game hitting .288 with 10 homers, 34 RBIs and 12 stolen bases while shoring up the defense in center field.

A healthy number of Braves fans in the crowd of 35,406 gave Grissom a big cheer. Grissom singled his next time up, stole second and scored. When he gave a postgame interview on the field, fans behind the dugout chanted his name.

“I just took a second to myself (before the game) to just really look at everything, and just do my best to just take a picture in my head,” said Grissom, who went back on the field with his family after the game. “You really don’t know until you actually do it. I mean, you try to prepare yourself and all that, but it’s nothing like how you think it’s going to be.”

Grissom was batting .324 with 14 homers, 67 RBIs and 27 stolen bases at Single-A Rome and Double-A Mississippi this season. He only played 22 games with the Mississippi Braves before getting the call-up to the majors.

His mother, father, stepfather, sister, aunt and girlfriend made the trip from Florida to see him play second base and bat ninth in his debut.

Grissom hit into a fielder’s choice in the third inning, struck out in the fifth, and came up again with one on and one out in the seventh, when he homered to make it 5-1.

Grissom added a single in the ninth; the Braves made sure to call for this ball as a keepsake (though the home run ball was eventually retrieved). He later scored on Dansby Swanson’s single to make it 8-4.

“He was like a kid out on the playground, pretty much just having a ball. I think they said it’s genuine. I think that guy really likes to play baseball,” Snitker said. “It’s a novel idea: Have fun playing baseball.”