OXFORD United were unable to finish the season on a high as Chris Wilder's Northampton Town swept to victory to preserve their Football League status.
It neatly summed up the U's season - after a promising start where Ryan Williams grabbed an early goal it fizzled out into a defeat.
There were plenty of nerves among the home fans after falling behind, but the picture changed when Williams was sent off for retaliation in the 19th minute.
John Marquis and Ivan Toney struck in quick succession and a third goal early in the second half from Mathias Kouo-Doumbe put the result beyond doubt.
Many of the United players will have come off wondering if it was their last display for the club, ahead of contract talks next week.
Injuries to Michael Raynes and Alfie Potter forced two of Gary Waddock's three changes.
Matt Bevans came in at right back as David Hunt moved into the middle, while Scott Davies started in midfield.
The other change saw Danny Rose make his first start for more than a month as Nicky Wroe dropped to the bench.
United, unlike their hosts, had nothing tangible to play for, but they started well.
James Constable had a shot well blocked inside 30 seconds and within six minutes the visitors were ahead.
The striker won a corner, which Rose swung into the near post. Both Dave Kitson and Tom Newey got touches, before Williams slammed in his eighth goal of the season from six yards.
A jubilant away end wasted no time in asking Wilder what the score was, but the Cobblers should have levelled within two minutes.
Toney ran clear, but Ryan Clarke ran out to force the teenager wide. With two men on the line the striker squirted a shot on to the post for Clarke the gather.
With Wycombe winning at Torquay, Sixfields grew increasingly tense.
Williams was enjoying himself, twisting past three challenges before firing just over from 20 yards.
But the Australian, making the final appearance in his loan from Fulham, blotted his copybook on 19 minutes.
Ricky Ravenhill came through strongly on the winger, who lashed out and referee Scott Duncan had no hesitation in producing a straight red card.
It gave added impetus to Northampton and Chris Hackett twice came close to an equaliser.
The momentum was with the hosts, who seized control of the game with two goals in four minutes.
Marquis robbed Jake Wright and showed composure as he ran through to slot past Clarke.
Sixfields breathed a sigh of relief and the home fans exploded again when Toney headed in Evan Horwood's cross.
The cushion could have been even greater at half-time, as Town were denied a third goal in stoppage time.
A sequence of four successive corners ended with Marquis having a shot which appeared to cross the line, but United scrambled the ball clear without the officials awarding a goal.
There was no doubt five minutes after the restart, when Northampton did make it 3-1.
Tom Newey conceded a free-kick, which Hackett swung in for Kouo-Doumbe to plant a header back across Clarke and into the corner of the net.
It gave the hosts some breathing space and the intensity of the game dropped.
Northampton were content to give United time on the ball in their own half, but they struggled to get support for Constable.
There were no chances to speak of as Cobblers goalkeeper Matt Duke spent much of the half as a spectator.
The home side did not throw men forward like they had before the break, but still looked the more dangerous.
Only a superb clearance off the line from Wright prevented Emile Sinclair from scoring on 71 minutes after the striker lobbed Clarke.
Gary Waddock introduced Callum O'Dowda and Tyrone Marsh to give United fresh energy, but the youngsters could do little to change a game which had long since got away from the visitors.
While the home side celebrated a great escape at the final whistle, United began what will be a long summer after suffering an 11th defeat in 15 games.
Northampton: Duke, Tozer, Diamond, Robertson (Kouo-Doumbe ht), Horwood, Hackett, Ravenhill, Carter, Morris, Toney (Dickenson 73), Marquis (Sinclair 62).
Unused subs: Snedker, Langmead, Deegan.
Oxford: Clarke, Bevans, Hunt, Wright, Newey, Davies, Rose, Ruffels, Williams, Kitson (O'Dowda 57), Constable (Marsh 75).
Unused subs: Crocombe, Meades, Wroe, Long, Shama.
Attendance: 7,529 (1,358 visitors).
Referee: Scott Duncan (Northumberland).