Jim Smith's first game back as caretaker boss proved a lot more successful than his last one as manager 13 months ago as the U's chalked up only their second away win of the season.

And it even came on Setanta!

A goal in each half from strikers James Constable and Jamie Guy did the trick at Field Mill last night with substitute Sam Deering sealing the points with a well-taken third following a dismal clearance from goalkeeper Paddy Gamble.

If Smith, or whoever takes over eventually, can get the Constable-Guy partnership working again, Oxford United's season may yet deliver something.

It was only Guy's third goal of the season, and his second in the league - and had all the hallmarks of his strength, power and directness which in pre-season had promised so much.

United had the boost of the an early goal, something they seldom got under Darren Patterson this season.

Chris Carruthers fired a cross over from the left and James Constable climbed well to head down and into the net from five yards.

It was leading scorer Constable's tenth goal of the season, and his ninth for Oxford.

Smith changed the system, using Joe Burnell and Carruthers as wingbacks and recalling Chris Willmott to one of the central defenders to play alongside Luke Foster and Matt Day.

The ground looked very empty at kick-off time, with many preferring to watch the game in the pubs than on a cold, damp night in Nottinghamshire.

The pitch had passsed an inspection earlier in the day because of some surface water, but it was perfectly playable.

Only a couple of minutes into the match, both trainers were on, tending to the wounded after a nasty-looking clash of heads involving Jason Lee and Eddie Hutchinson. Lee went off for stitches and returned with a bandage over his head.

Up front, Smith had gone back to the old partnership of Constable and Jamie Guy, and on 17 minutes, Guy showed a flash of that directness that can make him such a handful.

After what, in truth, was some pretty woeful defending, Guy cut positively in from the right side of the box but drove wide.

The Stags had had fleeting moments, Jonathan D'Laryea having a shot on the turn saved by Billy Turley, but when they equalised in the 21st minueit came out of the blue.

Chris Willmott was penalised for fouling Adnan Ahmed three yards outside the area. The visitors lined their wall up well enough but Nathan Arnold curled his 22-yard free-kick around the wall and just inside Turley's left post.

A few moments later, Foster gave away another free-kick in a dangerous position, but this time Mansfield over-elaborated and Guy raced clear with the ball.

Day's distribution from the back was often a problem for the U's. When put under pressure, he often gave the ball away, though he was at least prepared to have a shot from distance, and his long throw-ins were sometimes effective.

Carruthers took a bad knock near the left touchline in the closing minutes of the first half, and he went off for treatment, and didn't return. Sam Deering, rested from the starting line-up, replaced him for the second half.

Both sides created good opportunities from players gettiong to the bye-line at the start of the second half.

The dangerous Emile Sinclair got past three players and cut the ball back dangerously but Hutchinson threw himself in the way to block D'Laryea's shot.

Deering then did likewise but the Stags managed to defend it.

You often get the uinexpected from the skilful Deering, and few expected him to unleash a terrific 35-yard shot that Paddy Gamble got behind, but no doubt with his heart thumping.

Guy put United back in front on 57 minutes with a super goal.

Constable played the poass through and Guy, showing great strength, fended off Adie Moses, advanced and then thumped his shot low past the keeper.

Mansfield boss Billy McEwan was greeted with chants of "You Don't Know What You're Doing" when he substituted one of his team's better player, Ahmed, with 20 minutes to go.

Just a minute later, Deering latched onto Gamble's catastrophic error, and curled a shot around him from 18 yards.

Stags' late sub Mark Stallard almost pulled a goal back at the finish with a snap shot in a crowded box, which deflected and looked to be heading in. But Turley stuck out his right hand to make a fine reaction save.