Domingo German made baseball history with a heavy heart.

The Yankees right-hander threw the fourth perfect game in franchise history and 24th ever in major league history in the Bombers’ 11-0 win over the Athletics at Oakland Coliseum on Wednesday night.

German, after joining Don Larsen, David Cone and David Wells as the only Yankees pitchers to do so, revealed he completed the feat while mourning the death of his uncle.

YES Network’s Meredith Marakovits asked German in an on-field interview what was it about his stuff that allowed him to be perfect — not allowing a hit or walk on just 99 pitches.

“Unfortunately, two days ago an uncle of mine passed away and I cried a lot yesterday in the clubhouse,” German said through an interpreter. “I had him with me throughout the whole game. I was thinking about him and it happened.

“This game is a tribute to him.”

German, 30, struck out nine in the first perfect game in the majors since Felix Hernandez’s in 2012.

“He would be so happy,” German said of his uncle. “He was always someone who really brought joy to our family.

“And it happened for him to watch this from up there.”

This season hasn’t always been filled with happy outings for German, who lowered his ERA to 4.54 and improved his record to 5-5.

He was also suspended 10 games in May after using too much rosin on his hand during a game in Toronto against the Blue Jays.

Giancarlo Stanton gave German all the offense he needed on a night the Yankees’ bats came alive.

The slugger homered and drove in three runs.  

“So exciting when you think of something very unique in baseball,” German said. “Not many people have an opportunity to pitch a perfect game.

“To accomplish something like this in my career is something I’m going to remember forever.”