The 21-year-old currently plays for Polish side Jagiellonia Bialystok, but his agent has claimed that Genk have made a “more interesting” offer for the player.
"Celtic sent an offer, but Genk also sent an offer that was a little bit more interesting for the club," Radoslaw Osuch told BBC Scotland.
Bhoys manager Neil Lennon said he was aware of the bid, but was unsure what stage it was at.
"I'm not sure if it's a done deal, but we might be further down the line with that one. He's a goalkeeper we do like and we feel he has huge potential."
Celtic have maintained a 100 percent start to the new SPL season, with current keeper Lukasz Zaluska not conceding in their two games.