Lucas Akins's goal on the brink of half time was enough for Burton Albion to take all three points at the Kassam Stadium on Saturday afternoon.
Albion took the lead with just minutes of the first half remaining after Stuart Beavon squared the ball to Akins, who slotted home.
The Brewers began the second half as lively as they ended the first, with Akins causing the Oxford defence all sorts of problems.
Beavon sparked controversy in the 66th minute after dispossessing the goalkeeper and being brought down on the edge of the box, but the referee gave a free kick instead of playing advantage.
The Oxford net was empty and George Long was consequently booked for the offence, but nothing came of the resulting free kick.
Albion were ending the game strongly and looked to extend their lead, but the home side were able to keep the deficit to just one goal.
