Oxford heaped more misery on Blue Square Premier basement side Northwich with a comfortable 3-1 victory at the Kassam Stadium.
New U's manager Darren Patterson, who took over from Jim Smith just 24 hours earlier, saw his side dominate against a team who have yet to record a league win this season.
They moved swiftly into a seventh minute lead when Phil Trainer cut through the defence and supplied a cross that on-rushing wing back Alex Jeannin headed past visiting goalkeeper Scott Tynan.
But with Oxford looking comfortable, Northwich hit back when Luke Horrocks' excellent low cross evaded two defenders and was turned in by Danny Williams.
But just before the break Oxford were back in control when Yemi Odubade was taken down inside the box and got up to convert the resulting penalty.
The game was cagey after the break with both teams struggling to carve open any real opportunities.
Jeannin's acrobatic volley was saved comfortably by Tynan while Paddy Collins should have headed home one of the defender's dangerous corners.
But Oxford sealed the win with three minutes left on the clock when substitute Alex Fisher fired low across the six-yard box after a searing run and Eddie Anaclet provided an expert finishing touch at the far post.