Some sources suggest the Bafana Bafana star could be on his way to the Brazilians, while media reports circulating on Wednesday claim Moroka Swallows have also entered the race for the playmaker's signature.
The PSL Player of the Year in 2008 and 2009 has fallen out of favour with his Dutch boss this season, having started just four times for his club.
Modise trained with the rest of the squad at Johannesburg Stadium on Wednesday but is not expected to be on the bench as the Bucs attempt to make it five wins out of six against Santos on Saturday.
Asked by Football365.co.za whether the 28-year-old was likely to remain in Parktown at the start of February, Krol dropped a strong hint that Modise may be on his way out.
"I don't know whether he will be here next month. You will have to ask those on the board, not me," he said.
Pressed on whether the midfielder would feature against Santos this weekend, Krol gave a similarly uncommitted response.
"I'm not sure. We will have to see what team I select," he added.