Barnsley have confirmed Derby County have made an approach to sign Oakwell captain Jason Shackell.
Derby boss Nigel Clough is keen to bring in leadership over the summer and has reportedly offered £700,000 for Shackell.
The Tykes beat off competition from several clubs to sign Shackell for an undisclosed fee from Wolves last summer after he had spent the previous season on loan at Doncaster.
The defender made 44 Championship appearances for the Tykes this season but a decision on his future is unlikely to be made until a replacement for departed manager Mark Robins is found.
A Barnsley spokesman said: "We can confirm we have received an approach from Derby for our captain Jason Shackell, but we will not be making further comment until we have appointed our new manager."
Clough has already secured deals for Frank Fielding, Jamie Ward and Theo Robinson and is eager to bring in players with experience.
He told the club's official website: "We need some leaders. I think there have been two or three players carrying the load over the last year.
"There has been too much responsibility on them. We need more leader-type players spread around the team, which is something we are aiming to introduce next season."