Reds boss Simon Davey has confirmed Luke Steele will confirm a permanent switch from Premier League new boys West Brom this summer but a deal for Welsh defender Lewin Nyatanga may drag on.
Nyatanga rejoined Barnsley on loan in January from Derby County with a view to a permanent deal in the summer.
However Nyatanga played for Derby in their 4-0 defeat by Reading last Sunday and he may yet stay at Pride Park.
Davey told www.barnsleyfc.co.uk:
"Luke will sign for us on June 21 and will be here permanently for next season.
"To be honest I am not too sure about Lewin at the moment. He has gone back to Derby County and they have come down now so we might have to wait and see on that one.
"The deal is still there with Derby but there are ways to get out of it from both sides and at the end of the day it will come down to what the player wants to do.
Nyatanga is still likely to join however after Derby boss Paul Jewell told www.dcfc.co.uk:
"The large majority of these players if I have my way will never play for Derby County again.