Left-back Reece James scored on his return to the starting eleven to secure a hard-earned victory and move 15th-placed Rovers to within five points of the top six with games in hand.
Rovers were on the back foot for the majority of the contest but a resilient rearguard action provided the perfect response to the defeat to Sunderland.
“The game was won thanks to our work off the ball and everyone did their jobs,” said Moore.
“We had less than 48 hours to prepare for this game so a lot of our work was done in the classroom.
“In terms of that we got our tactics spot on. It took a lot of concentration, particularly after a Christmas period when bodies are weary and minds are tired.
“We had to show a different side to us to get the result.”
Oxford began brighter with Shandon Baptiste and Matt Taylor going close early on.
Rovers slowly grew into the contest and took the lead on 34 minutes with their first shot on target – James slamming home from an acute angle.
Taylor twice saw efforts cleared off the line in the second half as the visitors pushed for an equaliser but Rovers held firm.
Doncaster Rovers: Dieng, Halliday, Wright, Anderson, James, Sheaf, Whiteman, Taylor (Watters 64), Sadlier, Coppinger (Gomes 66), Ennis (Thomas 82). Subs not used: Lawlor, Amos, Greaves, Daniels.
Oxford United: Archer, Cadden, Dickie, Mousinho, Ruffels, Rodriguez Gorrin (Mackie 70), Baptiste, Henry, Fosu (Agyei 85), Sykes (Hall 70), Taylor. Subs not used: Moore, Long, Stevens, Lopes.
Referee: Sebastian Stockbridge (Tyne).
Attendance: 7,524 (759)