Conor McGregor told his dad that they "hold all the aces" as he wished him a happy birthday.
Tony McGregor had a bottle of Proper Twelve dropped off to his house as he celebrated the day.
Sharing an old photo with his dad, the UFC star said on his Instagram story: "Happy birthday Da. We hold all the aces."
The former two-weight champion is currently preparing for his trilogy fight with Dustin Poirier, which takes place in Las Vegas on July 10.
He has moved his training camp from Dubai to California in the past week as he puts the finishing touches on his preparations.
McGregor has been pictured cycling to training in recent days, with other snaps showing him bench pressing over 50kg.
The Dubliner says he feels very confident ahead of the UFC 264 contest, telling Fox Sports: "All the marbles are on the line. I'm here training very, very hard. I'm about to go for my second session of the day. I'm in great condition already.
"I beat him in the original bout [in 2014]. I lost in the rematch. And then we've got trilogy, I've got a few little adjustments to make.
"I feel very, very confident. I'm very focused and driven. And I'll go in there and put on one hell of a performance and get it back on July 10th."
Predicting how the fight will finish, McGregor added: "I'm gonna crack him with a jab and he's gonna wobble and I'm gonna put him away early. It is going to be a first-round KO, mark my words."
