Ozuna homered twice as the Braves tied the major league season record of 307 but lost their regular-season finale 10-9 to the Washington Nationals on Sunday as Jacob Young drove in two runs with a go-ahead single in the ninth.
Ozuna reached 40 homers with a ninth-inning drive off Kyle Finnegan. He had four RBI to reach 100 for the first time since 2017. He batted .274, remarkable final stats for a player who hit two homers in his first 18 games and was batting .189 on May 19.
"People didn't believe the way I believe in myself," Ozuna said.
When he walked in the seventh, he thought he wouldn't have another opportunity to hit No. 40.
"God gave me another chance, and I did it," Ozuna said, adding "it feels amazing."
"It's been a good year for a lot of us," said Matt Olson, whose 54 homers and 137 RBI led the majors. "It doesn't end now. This is when the fun starts."
Atlanta finished a major league-best 104-58 and opens the Division Series on Oct. 7 against Philadelphia or Miami. The Braves have scheduled intrasquad games from Tuesday through Thursday.
Atlanta also topped 100 wins last year, going 101-61 before losing to the Phillies in the Division Series.
Washington was last in the NL East for the fourth straight season, improving to 71-91 from 55-107.
Michael Tonkin (7-3) blew an 8-7 lead in the ninth, issuing a bases-loaded walk to Drew Milas that tied the score. Young followed with the two-run single.
Finnegan also gave up a double to Michael Harris II but finished the ninth for his 28th save in 36 chances.