Jake Paul has doubled down on his attack on Conor McGregor after the UFC star returned to training.
McGregor is completing his recovery from the broken leg he suffered in his trilogy bout with Dustin Poirier last summer.
He posted a video on social media of himself hitting pads with boxing gloves - and Paul was not impressed.
"This is embarrassing," he said on Instagram. "Your chin [is] wide open with no head movement for the Problem Child's right hand of God."
Paul then followed up his comments by dragging Jorge Masvidal into the argument.
"A new saying is, I feel bad for stupid people, they're so stupid they don't even realise they're stupid," said Paul.
"It's like people who think Masvidal is a good fighter; it's like the people who think Conor McGregor is still a good fighter.
"These guys haven't won fights in I don't know how the f*** long. They're over the hill, washed-up bozos and I'm going to knock them both the f*** out."
Masvidal lost his third fight in a row last weekend when he was outpointed by bitter rival Colby Covington.
That defeat followed successive losses against welterweight world champion Kamaru Usman.
McGregor, meanwhile, has won one of his last four fights - a 40-second demolition of Donald Cerrone two years ago.
The Dubliner has set his sights on a return this summer - and has demanded a shot at his old lightweight belt.
But his last win at 155lb came against Eddie Alvarez in 2016 when he was crowned the double champion.
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Charles Oliveira will defend the belt against Justin Gaethje on May 7 with Islam Makhachev hovering in the wings to face the winner.
But he could be forced to rearrange his fight with Beneil Dariush for the summer, leaving the door open for McGregor.
The 33-year-old has two fights left on his UFC contract and so could be available to fight Paul as soon as next year.
A bout with Masvidal appears less likely after the Miami resident signed a lucrative multi-fight deal with the promotion before his defeat by Covington.
Paul is likely to return to the ring in late summer with Tommy Fury among the possible opponents for his sixth professional fight.
