Deadly hitman James Constable bagged a brace as promotion chasers Oxford recorded a 2-0 victory over injury ravaged Mansfield at the Kassam Stadium.

The 25 year old has now increased his goal tally to 23 goals in just 39 starts, and he may have added further to that chart in the first half.

Stags' boss David Holdsworth was forced into wholesale changes through injury, including three adjustments to the backline. Steven Istead started at right back, with Andy Burgess slotting in at left back. The returning Luke Jones partnered Scott Garner in the middle of defence.

The reshuffle also meant a first start in ten weeks for Matt Somner and his midfield partner Gary Mills took the captain's armband. Ryan Williams returned to the side, as did striker Rob Duffy on his old stomping ground.

But it was Constable who wrote the headlines, with substitute Alfie Potter scoring high marks for his role as supporting artist.

Constable began his day's work by firing straight at Alan Marriott from 12 yards after a pass from the right.

Then Kevin Sandwith swung in from the left but Matt Green's diving header was off target at the far post.

In form midfielder Gary Mills started Stags' first charge at goal. He sent a delicate through ball to Jake Speight down the middle, but after a good turn, he got his shot horribly wrong.

There was little to trouble either goalkeeper in the opening 25 minutes, but Stags enjoyed taking advntage of the large Oxford pitch in the early stages, with some useful approach play.

Mills again threaded it through to Speight inside the area, and after using his strength to hold off his marker before turning to shoot, he forced a corner.

Sandwith then delivered from the left and somehow Matt Green failed to connect from only a matter of yards.

On 34, Adam Chapman struck a sweet curling effort from 20 yards and Marriott had to make a fine save, as he tipped it over the bar.

Chapman turned provider from a corner six minutes later, but the onrushing Kevin Sandwith was unable to convert at the back post as another U's chance went begging.

At the other end, Stags increased their corner tally, after a neat move involving Williams and Speight.

In the final minutes of the first half, Oxford's Simon Clist assited James Constable, but the hitman's goal bound effort was blocked on route to goal by defender Luke Jones.

Then Constable tried to bring the ball under control before firing well over from short range.

It was Constable who blazed wide in the opening minute after the restart, but his time was to come.

Damian Batt cut inside of Andy Burgess on the right with 53 minutes on the watch, before arrowing a shot into this sidenetting.

Substitute Alfie Potter skipped past two players before unleashing a shot which was aimed straight at Marriott, as the hosts continued to threaten.

Stags' defender Scott Garner made a vital intervention when he cut out Constable's pass inside the penalty area,

Then within the blink of an eye, Jake Speight missed a glaring chance at the other end. After being played in on goal by Briscoe, Speight, instead of shooting at goalkeeper Clarke, tried to feed Rob Duffy who was crowded by home players.

Stags' boss David Holdsworth made a double attacking change with 21 minutes left to play. Louis Briscoe and Rob Duffy made way for Jon Shaw and Kyle Perry.

Moments later, Potter struck into the side netting as Marriott was again left untested.

But Stags' number one was made to dive down low to hold a well-hit Potter strike only two minutes later.

Makeshift Mansfield had successfully contained their hosts until they were undone in the 73rd minute.

James Constable placed the ball beyond Marriott and into the corner of the goal after an eye catching Oxford break into the box which again involved lively substitute Potter.

Kyle Perry struck at goal two minutes later, but it lacked the accuracy and power to beat Ryan Clarke from over 25 yards.

Oxford's Potter was in the thick of the action again as he scurried down the touch line before whipping a cross for Midson to head down, which Marriott did well to save at his near post.

Blair Sturrock saw the last ten minutes of the encounter, replacing Jake Speight.

Oxford sealed the points on 86 minutes after fine work from Potter.

The diminutive midfielder used his skill on the goal line to pull back for Constable, whose deflected shot sailed into the net, with Marriott managing only to palm in vain.

Andy Burgess curled a 25 yard free kick well wide in the 89th minute as Stags' luck ran out.

Mansfield will now look to end their campaign on a winning home note next Saturday against Kidderminster Harries, while their away record this season reads: won 8, drawn three and lost 11.