The Frenchman, who left the Swans at the end of last season, has impressed Gills boss Andy Hessenthaler in pre-season friendlies.

Sidibe, 22, attracted attention last year with his skill and aerial prowess and Hessenthaler feels there is more to come from him.

He told BBC Radio Kent: "Mamady's still very young and has got a lot to learn about the position but once he's got the ball he's very dangerous.

"It's my job to coach him now and make him into a very good player.

"We see him as the future because we've got a lot of players who are 30-plus and we need to start bringing a few younger ones in."