OXFORD United were cruelly beaten by a last-minute Nicky Ajose strike as Manchester United XI won tonight's pre-season friendly at the Kassam Stadium.
The U's dominated the second half and deserved victory against their illustrious opponents after outplaying and outbattling them in the second half.
But Ajose latched onto an Oliver Norwood free-kick in stoppage time to deny them a draw - the least they deserved.
Although Ole Gunnar Solksjaer's side were all youth team players, they are all quality players, but couldn't live with the U's for most of the second 45 minutes.
Oxford fell behind to a poor goal on the stroke of half-time, only to equalise 30 seconds later.
A foul by Mark Creighton on the edge of the box saw Magnus Eiksem - who had seen an earlier penalty saved - strike a free-kick under the wall and past the outstretched hand of Ryan Clarke.
The Oxford keeper probably should have done better, and having seen a free-kick beat him in the draw with Leicester on Saturday, will be disappointed.
But credit Chris Wilder's side because straight from the kick-off they levelled.
A poor kick from Man Utd keeper Sam Johnstone was collected by Simon Heslop, who surged forward.
He fed Matt Green, who in turn played in Hall and from his cross, Constable turned the ball in from six yards.
It was another well-worked goal and again similar to his strike on Saturday.
While fingers may be pointed at Clarke for the goal, he was, however, Oxford's hero in the fifth minute, diving low to his left to keep out Eiksem's penalty after another Creighton foul.
Wilder made three changes from the U's starting line-up against Leicester on Saturday.
Jake Wright was not risked after coming off at half-time at the weekend, Harry Worley replacing him in the heart of the defence.
Jack Midson and Matt Green were chosen instead of Alfie Potter and Sam Deering alongside Constable in a three-pronged attack.
The Manchester United XI was made up entirely of youth players under the watchful eye of Ole Gunnar Solksjaer.
With the surface greasy after a torrential pre-match downpour, both sides struggled to keep the ball in the opening few minutes.
Oxford were fortunate not to fall behind after five minutes against Leicester when their opponents hit a post - and even more lucky last night.
A defence-splitting pass from Ravel Morrison set James Chester free, and although the midfielder had lost control of the ball, Creighton caught his legs.
Referee John Busby had no hesitation in pointing to the spot, and while Eiksem struck his penalty well enough, Clarke guessed right.
Constable did extremly well to beat two defenders in the penalty area soon after, and when it looked like he would shoot, the U's skipper instead tried to feed Midson six yards out, but he was inches away from latching onto his cross.
United's front three were posing problems and Matt Green saw a shot blocked, before skying the follow-up over the bar.
Midson was narrowly off target with a header from Simon Heslop's corner.
At the other end, Creighton was having a tough time, and from one poor ball back to his keeper, Clarke was in two minds what to do, and ended up diving on the ball as King closed in.
Incredibly, referee Busby deemed the backpass unintentional and waved play.
Morrison was proving influential for the visitors in central midfield, showing great feet and a variety of passes.
But it was Oxford who posed the main attacking threat.
Damian Batt's strong run ended with him being fouled 25 yards out. It was Batt who struck the free-kick that took a deflection, and was saved on the line at the second attempt by Johnstone.
To be fair to Creighton, after a torrid opening 20 minutes, he found his feet and made three crucial blocks - the last from a goal-bound Morrison shot.
However, less than 60 seconds later, Creighton fouled King right on the edge of the box and Eilsem fired the visitors in front.
And just another 30 seconds had passed before Constable had levelled.
Oxford started the second half very lively.
Green cut in from the right and hitting a left-foot shot that was well-saved.
Constable then saw a shot saved before the rebound got stuck under his feet, and Green struck the outside of a post when the ball fell to him.
Next it was defender Worley who surged forward. The former Leicester man played a neat one-two with Constable and went down in the box, but no penalty was given.
A rasping 30-yard effort from Heslop then flew inches over Johnstone's bar.
It was all Oxford and they were inches away from taking the lead through Green.
Constable did brilliantly to feed the forward, but with just the keeper to beat, Green saw his shot hit the same post and go wide.
Oxford looked to have a cast-iron penalty 15 minutes from time when Green was bundled over by two defenders, but the referee waved away their shouts.
Green was then denied by Johnstone and Constable saw his follow-up blocked as Oxford looked for a deserved winner.
Batt's fierce drive was then deflected over, before Asa Hall drilled in a left-foot effort that whistled just wide of an upright.
And although they couldn't find a winner, and Ajose's goal took a bit of the gloss off an impressive display, the majority of the 6,082 crowd went home very optimistic of what's in store.
Oxford Utd: Clarke, Batt, Tonkin, Bulman, Creighton, Worley, Heslop, Hall, Constable (Woodley 90), Midson (Deering 86), Green (Potter 86). Subs not used: Franks, Kinniburgh, Cole, Eastwood.
Man Utd XI: Johnstone, Wootton, Fryers (Stewart HT), Chester, Gill, Possebon, Ajose, Morrison (Tunnicliffe 84), King (Norwood 68), Eiksem (Lingard 78), Brady (Dudgeon HT). Subs not used: Devlin, Cathcart.
Attendance: 6,082.
Referee: J Busby (Oxfordshire).
Oxford Utd 1, Manchester Utd XI 2 (From Herald Series)
The U's dominated the second half and deserved victory against their illustrious opponents after outplaying and outbattling them in the second half.
But Ajose latched onto an Oliver Norwood free-kick in stoppage time to deny them a draw - the least they deserved.
Although Ole Gunnar Solksjaer's side were all youth team players, they are all quality players, but couldn't live with the U's for most of the second 45 minutes.
Oxford fell behind to a poor goal on the stroke of half-time, only to equalise 30 seconds later.
A foul by Mark Creighton on the edge of the box saw Magnus Eiksem - who had seen an earlier penalty saved - strike a free-kick under the wall and past the outstretched hand of Ryan Clarke.
The Oxford keeper probably should have done better, and having seen a free-kick beat him in the draw with Leicester on Saturday, will be disappointed.
But credit Chris Wilder's side because straight from the kick-off they levelled.
A poor kick from Man Utd keeper Sam Johnstone was collected by Simon Heslop, who surged forward.
He fed Matt Green, who in turn played in Hall and from his cross, Constable turned the ball in from six yards.
It was another well-worked goal and again similar to his strike on Saturday.
While fingers may be pointed at Clarke for the goal, he was, however, Oxford's hero in the fifth minute, diving low to his left to keep out Eiksem's penalty after another Creighton foul.
Wilder made three changes from the U's starting line-up against Leicester on Saturday.
Jake Wright was not risked after coming off at half-time at the weekend, Harry Worley replacing him in the heart of the defence.
Jack Midson and Matt Green were chosen instead of Alfie Potter and Sam Deering alongside Constable in a three-pronged attack.
The Manchester United XI was made up entirely of youth players under the watchful eye of Ole Gunnar Solksjaer.
With the surface greasy after a torrential pre-match downpour, both sides struggled to keep the ball in the opening few minutes.
Oxford were fortunate not to fall behind after five minutes against Leicester when their opponents hit a post - and even more lucky last night.
A defence-splitting pass from Ravel Morrison set James Chester free, and although the midfielder had lost control of the ball, Creighton caught his legs.
Referee John Busby had no hesitation in pointing to the spot, and while Eiksem struck his penalty well enough, Clarke guessed right.
Constable did extremly well to beat two defenders in the penalty area soon after, and when it looked like he would shoot, the U's skipper instead tried to feed Midson six yards out, but he was inches away from latching onto his cross.
United's front three were posing problems and Matt Green saw a shot blocked, before skying the follow-up over the bar.
Midson was narrowly off target with a header from Simon Heslop's corner.
At the other end, Creighton was having a tough time, and from one poor ball back to his keeper, Clarke was in two minds what to do, and ended up diving on the ball as King closed in.
Incredibly, referee Busby deemed the backpass unintentional and waved play.
Morrison was proving influential for the visitors in central midfield, showing great feet and a variety of passes.
But it was Oxford who posed the main attacking threat.
Damian Batt's strong run ended with him being fouled 25 yards out. It was Batt who struck the free-kick that took a deflection, and was saved on the line at the second attempt by Johnstone.
To be fair to Creighton, after a torrid opening 20 minutes, he found his feet and made three crucial blocks - the last from a goal-bound Morrison shot.
However, less than 60 seconds later, Creighton fouled King right on the edge of the box and Eilsem fired the visitors in front.
And just another 30 seconds had passed before Constable had levelled.
Oxford started the second half very lively.
Green cut in from the right and hitting a left-foot shot that was well-saved.
Constable then saw a shot saved before the rebound got stuck under his feet, and Green struck the outside of a post when the ball fell to him.
Next it was defender Worley who surged forward. The former Leicester man played a neat one-two with Constable and went down in the box, but no penalty was given.
A rasping 30-yard effort from Heslop then flew inches over Johnstone's bar.
It was all Oxford and they were inches away from taking the lead through Green.
Constable did brilliantly to feed the forward, but with just the keeper to beat, Green saw his shot hit the same post and go wide.
Oxford looked to have a cast-iron penalty 15 minutes from time when Green was bundled over by two defenders, but the referee waved away their shouts.
Green was then denied by Johnstone and Constable saw his follow-up blocked as Oxford looked for a deserved winner.
Batt's fierce drive was then deflected over, before Asa Hall drilled in a left-foot effort that whistled just wide of an upright.
And although they couldn't find a winner, and Ajose's goal took a bit of the gloss off an impressive display, the majority of the 6,082 crowd went home very optimistic of what's in store.
Oxford Utd: Clarke, Batt, Tonkin, Bulman, Creighton, Worley, Heslop, Hall, Constable (Woodley 90), Midson (Deering 86), Green (Potter 86). Subs not used: Franks, Kinniburgh, Cole, Eastwood.
Man Utd XI: Johnstone, Wootton, Fryers (Stewart HT), Chester, Gill, Possebon, Ajose, Morrison (Tunnicliffe 84), King (Norwood 68), Eiksem (Lingard 78), Brady (Dudgeon HT). Subs not used: Devlin, Cathcart.
Attendance: 6,082.
Referee: J Busby (Oxfordshire).
Oxford Utd 1, Manchester Utd XI 2 (From Herald Series)