Wycombe player-manager Gareth Ainsworth says he is targeting a top-half finish after Joel Grant's brilliant winner at the Kassam Stadium.
Grant struck the only goal, his 10th of the season, with a magnificent solo effort in the 19th minute. It meant Wycombe moved to just a point behind Oxford in the middle of the npower League Two table.
"I believe we can finish top half, and if we did, that would be a fantastic achievement for everyone at Wycombe, when you consider we were bottom of the league in November," Ainsworth said.
"We did exactly as we set out to do. Oxford threw a few difficult formations at us during the game, and we had to react. That's where I listened to my assistants, Richard Dobson and Lee Harrison, who have a lot of experience.
"I'm learning all the time as a manager, and I'm learning new formations, and they have helped me out. We looked really strong, and it was a fantastic goal from Joel - out of this world. Joel Grant's a match winner, I've always said that. But what I liked was his tracking back and his defensive work as well.
"We're nowhere near the finished article yet, I know that, but I'm just really enjoying working hard to improve us, and am enjoying learning so much all the time."
Oxford missed their chance to get back into the game when Tom Craddock headed Jon-Paul Pittman's cross over the bar from four yards, and then sliced another very presentable opportunity.
Craddock showed his displeasure at being subbed early in the second half by walking straight down the tunnel without acknowledging his replacement or anyone else.
Oxford manager Chris Wilder admitted he was "disappointed" with the striker's reaction, but said he was just one of several U's players who are totally down on confidence at the moment. Oxford have managed just one point from a possible 15 and their season is petering out painfully.
Wilder said: "We started brightly in the first 15-20 minutes and I thought then we were the better side. I'm critical of a bit of bad defending for the goal, but give the boy a bit of credit too - it was a top finish. After a bright spell again at the start of the second half when we couldn't score, the confidence just seemed to drain out of our players."