Fireworks night started early in The Bronx on Monday night, as Harrison Bader hit a three-run, go-ahead homer in the bottom of the eighth inning to spark the Yankees’ 6-3 win over Baltimore.

After trailing 3-0 in the third, the Yankees got back in the game with back-to-back homers by Anthony Volpe and Kyle Higashioka with one out in the fifth and tied the game on a wild pitch in the seventh.

And then Bader provided the biggest blast of the night against second-place Baltimore, as the Yankees opened a seven-game homestand with a win.

“The Bronx showed up with energy,’’ Bader said of the sellout crowd of 46,015.

Giancarlo Stanton started the winning rally with a rocket single to center to begin the bottom of the eighth. Anthony Rizzo then singled through the right side of the infield off lefty Danny Coulombe to send pinch-runner Oswaldo Cabrera to second.

Bader came up and drilled a hanging sweeper deep into the seats in left.

“He makes our lineup tougher,’’ Aaron Boone said. “He’s a really good competitor.”

Bader credited a pep talk from Aaron Judge during the middle of the game that helped him stay focused before his final at-bat that proved to be a game-changer.

It came against an Orioles team that is now three games ahead of the Yankees in the wild-card standings, no longer the punching bags from Camden Yards.

The Yankees had Domingo German on the mound for the first time since his perfect game in Oakland.

German retired the side in order in the first, but his run of perfection ended quickly in the second, when Ryan O’Hearn led off with a single to center and moved to second on Bader’s error.

Ramon Urias followed with a base hit to left, putting runners on the corners with no one out and Cedric Mullins drove in the game’s first run with the third straight hit off German.

Ex-Yankee Aaron Hicks then came to the plate and received a loud chorus of boos from the crowd and popped to third.

Higashioka picked off Urias at second base and German got Adam Frazier on a comebacker to keep it a one-run game.

German’s night ended after back-to-back singles with one out in the fifth.

He left to a loud ovation and acknowledged the crowd who were celebrating his perfect game — and not another shaky outing at home, having allowed nine hits — but he limited Baltimore to three runs, two earned.

Nick Ramirez entered and struck out O’Hearn and got Mullins on a groundout, as the lefty retired all five batters he faced. Ramirez was the first of four Yankee relievers who combined for 4 ²/₃ scoreless innings.

Volpe, who lined out to the warning track in left-center to lead off the bottom of the third, crushed a solo shot with two outs in the fifth. Higashioka, after doubling off Wells in the third, made it back-to-back homers for the Yankees to cut the deficit to 3-2.

Ian Hamilton escaped damage in the seventh when Volpe snared O’Hearn’s low liner to strand a pair of runners in scoring position.

In the bottom of the inning, Isiah Kiner-Falefa and Volpe singled off Mike Baumann.

Higashioka, who scalded the ball in his two at-bats, bunted the runners over and DJ LeMahieu had to face tough right-hander Yennier Cano.

With the infield in, LeMahieu hit a comebacker and Kiner-Falefa was thrown out between third and home.

But Cano bailed out the Yankees with Torres at the plate, as he fired a wild pitch that scored Volpe to tie the game.

Torres lined out to first to end the inning, but the Yankees came alive in the eighth.