The 23-year-old French-born midfielder is currently playing the African Cup of Nations with Mali, but on Sunday he should quickly fly to Turin, take his tests and return to Ghana, where the tournament is being held until February 10. He should join Juve at the latest by mid-February.
Juve are said to have settled on a transfer fee of 13 million euros (19 million dollars), while offering the player a four-year contract worth 2.5 million euros per season.
Swedish defender Olof Mellberg, 30, is also arranging his relocation from Aston Villa to Juve on a transfer deal of 850,000 euros when his contract with the English club runs out in the summer.
During the winter market, which closes on January 31, Juve should also sell Portuguese midfielder Tiago Mendes to Tottenham Hotspur and French defender Jean-Alain Boumsong to Olympique Lyon while Argentina's Sergio Almiron appears to be on his way to Monaco.