Plymouth striker Alex McDonald is set to feature before his second loan spell at Home Park comes to an end.
The 22-year-old Burnley man will return to Turf Moor after the last 16 tie with the U's having spent three months in Devon.
McDonald has made 14 starts for the Pilgrims since returning on loan, having helped Carl Fletcher's men avoid relegation in the second half of last season.
Captain Darren Purse will serve the final game of his three-match suspension after a straight red for a clash with Fleetwood's Jamie McGuire while Bournemouth loanee Mark Molesley is available to feature having not featured in the competition this season for the Cherries.
The 31-year-old made his debut in the 1-0 home defeat by Chesterfield and caught his manager's eye.
"He's experienced and he has played in this league before," Fletcher told their official website.
"He showed some real good and energy and quality, keeping the ball and making forward runs. He was obviously knackered at the end, but we're really pleased to have him here."
Oxford's preparations have been dealt a double blow with the news that Jon-Paul Pittman and Andy Whing are out for at least a month.
The duo were stretchered off either side of half-time in Saturday's 3-3 draw at Accrington in the FA Cup second round and Pittman (shoulder) and Whing (knee and ankle) will now undergo scans to determine the extent of their injuries.
Striker Tom Craddock has not featured since early November after suffering a cracked rib but he is rated 50/50 to make his comeback in the cup-tie with Plymouth which has proved a profitable one for goalscorers with an average of over four goals a game being scored since the early 1990's.
Meanwhile centre-back Michael Duberry is edging closer to a return to action but this game will come too soon for the experienced defender.