Manchester United chiefs have been meeting with Juventus officials in London since Thursday in a race to complete the deal before next week’s deadline.
The majority of terms are thought to be agreed, including Romelu Lukaku’s switch to the Serie A club in exchange.
However, Dybala is still uncertain about whether he should take the risk and move to a side who cannot guarantee Champions League football.
And now there is a further stumbling block which is stalling the deal.
According to Friday’s edition of Italian newspaper La Gazzetta dello Sport, Antun has claimed he can get the transfer boxed off for a substantial fee.
But the £13.7m sum requested has made the Red Devils reconsider their options.
The amount would be added onto any cash fee which United may have to pay Juventus, along with sending £75m forward Lukaku to the Old Lady.
All in all the deal is starting to look extremely expensive for a player with no Premier League experience.
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Meanwhile, Italian football expert Paolo Bandini says United must adjust their tactics to suit Dybala if they get the deal over the line
“Personally, this is what I’m saying about the Lukaku, Dybala deal – I think it can work for both of them,” Bandini said.
“I don’t think he has suddenly lost his talent.
“He is still a guy who’s scored extraordinary goals and scored really important goals at times in the Champions League.
“He’s someone who’s shown up in some huge matches before but he just hasn’t been able to, over the last two seasons, produce that consistency for Juventus.
“Certainly since Ronaldo arrived he’s really looked like someone who doesn’t have a spot in that team.
“I think his technicality, his pace, his speed of thought, could serve him really well in the Premier League.
“I think he could be a fascinating fit in the league, whether or not United are ready to make the most of him, well that’s internal stuff at the club that they have to work out.
“So for me yes, I think it would be a good signing for United because why not? I think you’ve got the potential for something better than what you have.”