Rantie had a great season with Pirates, winning the League, Telkom Knockout and MTN8, and the Buccaneers are engaged in talks with his Swedish club for a permanent deal.
Sundowns recently signed Eleazar Rodgers from Santos for a reported R7-million.
A source close to Rantie tells KickOff.com that Hassleholm do not want to sell the player to Sundowns.
"Sundowns have nine strikers so it will be career suicide if Rantie joins them while his career is on the rise," our source says.
"The club in Sweden knows that, and the player knows this too, and that is why talks have only been between Pirates and Hassleholm.
"But the problem with Pirates is that they have made an offer of R1.5-million and that is peanuts to a European club.
"So if Pirates don't meet the right price, then Rantie will move back to Sweden and join another club – but definitely not Sundowns."
Follow me on Twitter @ZolaDoda