Dobie returns from a three-game ban, but fellow forwards Joe Anyinsah and Gary Madine remain doubtful.
Anyinsah is struggling with a stomach/groin problem and Madine missed the midweek defeat at Colchester due to illness.
New loan signing Darryl Duffy, from Bristol Rovers, made his full debut at Colchester and is expected to retain his place up front.
Ben Marshall, also a deadline day loan signing from Stoke, was a second-half substitute and will hope to feature again.
David Raven (hip), Andy Cook (foot) and Gavin Rothery (double hernia) remain long-term absentees, while Richard Offiong, Marc Bridge-Wilkinson and Tom Taiwo are all pushing for a return to manager Greg Abbott's starting line-up.