Sunderland have been linked with Barnsley defender Alfie Mawson.
The Black Cats are among a number of Premier League and Championship clubs said to be interested in the former Brentford player, 22.
Barnsley head coach Paul Heckingbottom, the ex-Sunderland defender, told the Sheffield Star: “There’s interest for him and it’s fair to say that interest is growing.
“He was a League One defender last year, he’s a Championship defender this year and the longer he’s in the Championship the longer people can see what he’s about.
“There’s going to be interest and it’s expected. It has to be a no until you have someone to come in and replace them. We want the strongest possible team and we want to stay up.
“From a personal point of view, I’d like to keep Alfie here forever but that’s probably not going to happen.”
Barnsley, who impressed in defence in winning promotion via the League One play-offs last season, face Yorkshire rivals Huddersfield in the Championship today.