Brian Stock could leave the Keepmoat Stadium in January after contract talks with Doncaster were placed on hold. The 28-year-old skipper has played a key role in Rovers' promotion from npower League One and subsequent progress in the Championship during his four years at the club.Stock said "I'd be upset to leave the club. I've enjoyed a lot of success here and seen a lot of changes and I think that I've been part of that."I've had a good four years at Doncaster Rovers and if I do leave I'll leave with my head held high."Whether my future is here or elsewhere I need to secure my future because I've got two young children to support and football is only a short career."Stock began his professional career at Bournemouth and joined Preston for an undisclosed fee in January 2006 before arriving at Doncaster on loan the following September. Rovers paid £150,000 to make the move permanent in January 2007.