Oxford's injury problems have worsened.
Lee Cox, Michael Raynes and Wayne Brown all had to be replaced during the club's 3-2 win over AFC Wimbledon in midweek and are major doubts.
Cox was forced off with a groin problem at half-time, Raynes lasted just over half-an-hour before suffering a hamstring injury while goalkeeper Brown came off on the hour mark with another groin complaint.
Jon-Paul Pittman remains sidelined with a hamstring injury while Michael Duberry (neck), Liam Davis and Andy Whing (both groin) are still in the treatment room.
But there is a bit of respite for manager Chris Wilder as Adam Chapman, who has missed the last three games, returns from a foot injury and he can call on regular number one Ryan Clarke to start in goal.
Charlie Allen and Danny Jackman are both suspended for Gillingham.
Allen was given his marching orders in injury-time of Tuesday's 2-1 win at Northampton having picked up a second yellow card and now serves a one-match ban.
Fellow midfielder Jackman, meanwhile, serves the second game of a three-match punishment for his red card against Rochdale last weekend.
But manager Martin Allen is boosted in the middle of the park by the return of Bradley Dack following a three-match suspension of his own.
Charlie Lee continues to miss out with his leg injury, but Jack Payne made an earlier than expected return in midweek and is likely to start once again having netted the winner at Sixfields.
Oxford had lost six successive matches in League Two prior to their 3-2 win over AFC Wimbledon on Tuesday.