Oxford chairman Firoz Kassam has moved manager Graham Rix to an upstairs role at the U's, with youth coach Darren Patterson taking over the first team. Oxford have suffered a poor start to the season and were dumped out of the FA Cup by Rochdale on Saturday.
"Graham has done a good job and bought some good players but results have gone against us and we need to make changes," Kassam told their website.
"Graham assumes an upstairs role and Darren will take over the first team."
He added: "I have an excellent working relationship with Graham and hope that we can find a way to utilise his experience and knowledge at the club.
"Darren takes charge for the next three weeks and I have every faith in him and David Oldfield, who will remain first-team coach."