Kelly returns to action having served a six-game ban for pushing a ball boy against Plymouth in February but is available as the O's look to bounce back from their 5-0 defeat at Accrington in midweek.
Midfielder Sammy Moore is out through injury, while Robbie Weir remains sidelined with ligament damage.
Jens Janse, Paul McCallum and Aron Pollock are long-term absentees.
Doncaster boss Darren Ferguson has no major new injury concerns but has hinted he could make changes.
Rovers beat Notts County in midweek to extend their lead at the top to six points, but Ferguson is mindful some players might need a rest as they approach a third game in seven days.
Midfielder Gary McSheffrey, fully recovered from a long-term knee injury, defender Mitchell Lund and striker Andy Williams are all pushing for starts after stepping off the bench on Tuesday night.
Striker Liam Mandeville (thigh) remains doubtful, while Joe Wright, Aaron Taylor-Sinclair and Lee McCullough (all knee) are still out.