The player's Polish agent, Grzegorz Bednarz, expects to hear by Thursday if Celtic want Gancarczyk but admitted that fitness remains both his and the player's prime concern.
"Seweryn finished last season early in December, then had six weeks off," said Bednarz. "He only started preparations with his Ukrainian side for the new season nine days ago, straight after recovering from flu.
"It was heavy, conditional training during their camp in Dubai, so he's not in his best shape yet. We talked several times after his first practice with Celtic. He said it was fine, but he couldn't find a breath at the end.
"Normally, he has 'iron' stamina and great fitness, but you can't cheat your body."
Reports in Poland put the three-times-capped defender's transfer value at £750,000 but Metalist's sporting director claimed yesterday that any fee has still to be agreed.
"Celtic expressed a desire to invite Gancarczyk for a trial and medical examination," Metalist's Yevgeny Krasnikov said. "We agreed to that but we have not yet discussed his transfer fee."