Derek Jeter On Signing Andy Pettitte's Son To Marlins Deal, 'He's Got Good Genes!'

Does a good fastball run in Pettitte blood? Derek Jeter is certainly hoping so ... 'cause the Marlins exec said he signed Andy Pettitte's son this week because he's banking on the kid's DNA!!

Jeets spoke about the Marlins' deal with Jared Pettitte out in NYC to Adam Glyn ... explaining, with a little bit of his tongue in his cheek, that he inked Andy's boy 'cause of his legendary pops' skillset.

"He's got good genes," Jeter said wryly when asked why he thought his longtime Yankees teammate's son deserved a chance in the Miami org.

Of course, the younger Pettitte is much more than just Andy's kid ... he's got a live arm -- even though he did record a 5.81 ERA in 13 games at Dallas Baptist University this year.

"I do model a lot of my game after [my dad]," Jared told YES Network earlier this month. "I really have to rely a lot on command and just kind of the movement on my pitches."

Jared did not get picked in the 2021 MLB draft ... but Jeter was still able to get him on board as an undrafted free agent this week nonetheless.

And, when asked if he was emotional about being reunited with another Pettitte after having so much success with Andy in New York ... Jeter said he's taking a wait-and-see approach for that.

"Not yet," Jeter said. "We got to get him down there [in the minor leagues] first!"