New Dutch right-back Marciano Bruma is a doubt for the season's opener against Coventry City at Oakwell after breaking his hand in training.
Bruma, who arrived this summer from Sparta Rotterdam suffered the break after fellow new boy Dominik Werling stepped on his hand during a collision.
Reds boss Simon Davey told the Official Website:
"Marciano has broken his hand. It happened in a challenge with Dominik (Werling), who stood on his hand after a challenge.
"It is unfortunate and it looks as though he will need to have it pinned although he will meet with the Doc today and see a specialist later this week.
"We will have to wait and see how long it will take although there is still the possibility of Marciano wearing a protective soft cast in games. We will know more soon".
Meanwhile young defender Thomas Harban has joined Paul Heckingbottom on loan at League Two Bradford City until 1st January and Peruvian recruit Miguel Mostto is finally set to make his bow when The Reds face Rotherham in a friendly on Saturday.