Mattis is currently on loan at the Bescot Stadium and the club were bottom of League One before his arrivial. Since then though Walsall have won 3 games in a row to surge to 10th in the league!
Reds boss Simon Davey said he would be open to offers.
Tuesday's Sheffield Star reports:
BARNSLEY boss will listen to offers from Walsall for Dwayne Mattis.
League One Walsall are unbeaten since the 26-year-old joined on loan on September 28 and it is understood that manager Richard Money wants to make the move permanent. Said Barnsley boss Simon Davey: "Every player on the planet has a price. I'll listen to what the have to say."