Rob Duffy climbed off his sickbed to score a brilliant winning goal as Oxford United got their promotion challenge back on track with a first league victory since November.

On Friday, United's leading scorer went down with the virus which has affected many of his teammates, and physio Neil Sullivan was among those who didn't think he'd be able to play.

But, worried about losing his place to Marvin Robinson, Duffy said he would like to give it a go, and manager Jim Smith gambled on him.

And both decisions paid off as Duffy became the first Oxford United player to reach 20 goals in a season since Nigel Jemson ten years ago.

He headed home a superb goal on 36 minutes to bring second-placed Oxford their first Conference victory in 12 attempts.

Fourth-placed Gravesend could have gone above United had they won, but their hopes of mounting a second-half recovery all but ended when defender Peter Hawkins was sent off on the hour for a second yellow card.

Hawkins went hard into the back of Duffy, and he'd already been booked for a first-half foul on Yemi Odubade.

There was a new face in United's squad, Luke Foster, signed late on Friday after impressing on trial, named as defensive cover on the bench.

The visitors made a good start, playing the ball around, with confidence after their seven-game unbeaten run, and with Charlie MacDonald looking very lively.

Former Oxford midfielder Rob Quinn had to leave the pitch for three minutes for stitches in a head wound, but even during this time, ten-man Gravesend still kept the ball and applied all the pressure.

A few minutes later, MacDonald got around the back of Oxford's defence to pull back a cross, but Quinn screwed his shot wide, the ball deflecting away for a corner.

It took United some time to really get into the match, but they gradually got their passing going, and spread play well.

For a while it was United who were looking more like the away side and playing on the counter-attack, and one promising raid ended when Danny Rose overhit his defence-splitting pass to Odubade.

At the other end, Stacy Long finished off one move from the visitors by hitting a low drive at goal, but the ball virtually trickled towards goalkeeper Billy Turley.

Long went closer after playing a one-two at a short corner, when his inswinging cross flew over Turley and hit the top of the crossbar.

The pace of Odubade was giving Oxford a cutting edge when they attacked, and Hawkins was yellow-carded for bringing the speed merchant down when he was in full flow.

The U's went close to breaking the deadlock on 31 minutes when Martin Foster chipped in a cross from the right bye-line and Chris Hargreaves rose above his marker but saw his header skim off the bar.

Yet five minutes later, they did find the net - and it was a quality goal.

Gavin Johnson worked the ball down the left touchline to Rose, who drove over a superb cross for Duffy, who looped a header over Cronin and into the goal from 12 yards.

Oxford had not kept a clean sheet for seven matches and they were looking nervy at times at the back, Turley adding to the home fans' anxiety by dropping a simple catch from a corner.

The attacking strength down the right of Joel Ledgister was impressive for Gravesend, and from his cross, MacDonald almost turned the ball in.

Phil Gilchrist then cleared only as far as Mark DeBolla, whose low drive flashed across the face of goal and only two yards wide.

Ledgister was influential at the start of the second half, too, as he got past Gilchrist with ease on a sprint down the right before firing in a fierce shot that Turley did well to turn for a corner.

Oxford were now starting to get a grip on proceedings, but poor decision-making let them down.

Odubade crossed when he should have shot, with the goal beckoning, and later when he whipped in a cross from the right, the lurking Eddie Anaclet decided to hang back rather than make a run to the near post.

Gravesend had a big let-off when Odubade was brought down in the box by Paul McCarthy just as he was about to shoot.

The ref looked across to his assistant for guidance, but the linesman didn't want to know about a penalty.

They were the kind of decisions the U's were getting in the first four months of the season, but have seldom got since December.

Fleet were on the back foot even more after Hawkins's dismissal, but eight minutes from time they almost equalised on a fast break from defence.

MacDonald got past Mickey Corcoran and Barry Quinn and his angled drive was parried, with some difficulty by Turley. Ledgister came in on the loose ball, but rifled his shot into the side-netting.

United had to defend resolutely in the closing minutes to hang onto the three points, but they did so, with Gilchrist and Corcoran taking no prisoners.

And the home fans' cheer of relief at the final whistle could probably be heard right across the city.