The striker made an impressive contribution when he came off the bench to make his debut in Saturday`s 2-1 reverse to Preston, inspiring a fightback which came close to snatching a deserved share of the spoils.
After the game, manager Aidy Boothroyd said: "He (Marlon) has given himself a good chance of starting on Tuesday. He's focused and very much looking forward to playing a key part in what we are doing here."
The Sky Blues boss may opt to make make or two changes elsewhere following Saturday`s defeat, although he was anything but disappointed with his side`s efforts as they dominated North End only to be thwarted by keeper Andy Lonergan.
Gary McSheffrey, Danny Ward, David Bell and Michael McIndoe are all pushing for starts, but the likes of Freddy Eastwood (knee), James McPake (shin) and Gary Deegan (ankle) remain in the stands.