Yann M'Vlla is now in England having landed at London Heathrow as Sunderland hope to conclude a deal.
M'Vila has been left out of the Rubin Kazan squad for their Premier League season amid ongoing talks with Sunderland.
The midfielder spent last season on loan at the Stadium of Light and impressed, helping Sunderland escape relegation.
The Frenchman made 37 appearances league appearances for the Black Cats in their last campaign.
David Moyes is looking for further reinforcements to his Sunderland team, with his side sitting 16th in the league.