Hatters boss Ray Harford named an unchanged side from the one that had extended their unbeaten run to seven matches in the FA Cup fourth round win over Southampton a week earlier.
Brian Stein and Ian Allinson had scored the goals in that 2-0 win and both started as part of a four-pronged attack, with the younger Stein brother, Mark, and Town talisman Mick Harford leading the line.
Goalkeeper Les Sealey, right-back Tim Breacker and captain Steve Foster maintained their ever-present status by making their 31st starts of the season for the Town, who sat eighth at kick-off.
For third-bottom Oxford, manager Maurice Evans was without centre-half John Dreyer - who would join the Hatters the following season - through injury, but he had Wales international Dean Saunders, who would go on to partner Harford at Derby County a couple of years later, up front.
Former Hatters keeper Alan Judge was overlooked in goal for Steve Hardwick, an ex-Newcastle United team-mate of Harford's, but knew he would be back in for the midweek Littlewoods Cup semi-final first leg due to Hardwick being cup-tied having appeared for Sunderland earlier in the season.
TOWN: Sealey, Breacker, Johnson, Donaghy, Foster (c), McDonough, Wilson, B Stein, Harford, M Stein, Allinson.
Subs: Grimes, Black.
OXFORD: Hardwick, Bardsley, Hill, Shelton, Briggs, Caton, Hebberd, Foyle, Saunders, Phillips, Rhoades-Brown.
Subs: Mustoe, Whitehurst.
REFEREE: Noel Butler