ATLANTA — After getting bludgeoned the previous night, the Mets were off to a rough start Sunday, with their best starting pitcher unsteady.

But the long afternoon that appeared to await Nolan McLean and the Mets never materialized, as the rookie right-hander recovered to help lead a 10-9 victory over the Braves.

Both Mets wins on this road trip have come in games started by McLean, a bright spot in a rotation besieged by underperformance.

McLean allowed three runs (one unearned) in the first inning and then nothing over the next five.

Overall, he surrendered five hits and one walk with five strikeouts.

The Mets, who won for only the third time in 15 games, will try to escape with a series split Monday before beginning a homestand that will take them to the All-Star break.

As badly as the Mets (37-53) have played against most opponents, they are 3-3 against the Braves, leaders of the National League East.

Bo Bichette’s RBI single in the first got the Mets started after Francisco Lindor reached on Austin Riley’s error and Juan Soto singled — and subsequently was thrown out attempting to stretch the hit into a double.

McLean had a rough first inning, allowing four hits, and didn’t help himself with an errant pickoff throw that led to an unearned run. Michael Harris II continued his big series with a two-run single and reached third when McLean’s pickoff attempt sailed past Mark Vientos. Mauricio Dubón’s RBI single extended the Braves lead to 3-1. Drake Baldwin was hit by a pitch leading off, and Ozzie Albies doubled him to third.

A.J. Ewing homered leading off the second against lefty Martín Pérez, but the Mets were just getting started. Luis Torrens walked and Brett Baty doubled before Lindor’s RBI single tied it 3-3. Soto followed with a two-run single, giving him 43 RBIs this season.

Vientos’ fielding error on Jim Jarvis’ grounder gave the Braves a leadoff baserunner in the fifth, but McLean overcame the miscue by recording three straight outs.

Tyrone Taylor homered in the ninth — his second straight game with a blast — to give the Mets a 6-3 cushion. Taylor went deep against former Met Carlos Carrasco.

Before the inning was complete, Bichette and Jared Young each delivered a two-run double, extending the lead to 10-3.

Huascar Brazobán got only one out in the ninth before he was removed. The Braves scored five runs against the right-hander, highlighted by Baldwin’s grand slam. Devin Williams was summoned to record the final two outs for the save after another run scored.

Williams struck out Dominic Smith with the tying run at third base and the winning run at second to end it.