Kiwi UFC star Israel Adesanya has been slammed by fans after taunting the son of his rival Alex Pereira after his knockout win at UFC 287 yesterday.

Adesanya reclaimed the middleweight title after impressive stoppage win over the Brazilian at the Miami event.

The Nigerian-born Kiwi then made a point of staring straight at Pereira’s son in the crowd who was left in tears.

Adesanya admitted the move was revenge for the way Pereira’s son acted when he lost the first bout.

“I’m petty. I remember. The first time he knocked me out in Brazil, his son came into the ring and then just started to lie dead next to me,” Adesanya said after the win.

“I’m like, ‘You f***ing little a******, I’ll whoop your ass if your dad don’t do it for you’.

“I looked for his kid, I pointed at him, and I saw him and I was like, ‘Hey, hey, hey’, just to remind him.”

Adesanya was called out for his action on social media.

“NAH Izzy is cold, lmao and for Adesanya to look at Pereira’s son and get revenge for something he did when he was 10 by taunting him after knocking his dad out is wild petty,” one fan said.

Another added: “Not OK … Izzy is so pathetic.”

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“Bro really beefin’ with a little kid,” another fan added.