The report claims, The Uruguayan need extras funds for new signings in January and he has decided to sell their duo midfielders in order to help the Black Cats from relegation.
The manager has already had a conversation with Cattermole regarding his poor record in his career following with eight red cards.
As per the reports, the manager is all set to replace them with more experienced midfielder in January transfer window.
Sunderland are currently sitting second from the last (19) in the league table.
The 25-year-old Cattermole, who arrived Stadium of Light in 2009 from Wigan Athletic and since then he has appeared for 83 times for the Black Cats.
The 27-year-old Gardner has joined The Rokerites from The Championship side Birmingham City in 2011.
Sunderland to host Chelsea on Wednesday, 07:45 PM – GMT.