Oh, brother!

Marlins lefty reliever Brian Moran struck out his brother, Colin, in the pitcher’s major league debut during Thursday night’s game against the Pirates.

The 30-year-old, who starred at Iona Prep, entered the game in the fourth inning and froze his brother on a 3-2 slider.

They became the first siblings in MLB history to face each other in a pitcher-batter scenario with one of the brothers making his debut, according to Elias Sports Bureau.

Brian hadn’t given up on his big-league dream, bouncing around the minors and the independent leagues before finally getting the call. As for Colin, the 26-year-old third baseman came into the game with a .286 average, to go with 17 home runs and 77 RBIs. He has played in the big leagues for four seasons.

During an interview on “Intentional Talk,” earlier in the series, Colin and Brian joked about the potential for this brotherly battle.

“I know if I face him, I’m going to try to take him deep,” Colin said.

“I wouldn’t expect anything else,” Brian interjected with a laugh.

“We‘ve been joking about this for years at the holidays or anything like that,” Colin said. “I don’t know, in the back of my head, I never thought it would actually happen. Figured it would happen at some point.

“Kind of crazy it could be on the big-league field for the first time.”

Though Colin has had the more productive career thus far, it looks like Brian will have Thanksgiving dinner bragging rights.