May 16, 2010: Oxford United 3, York City 1

IF, or when, Oxford United eventually reach the Sky Bet Championship it will follow several seasons of steady progress on and off the pitch.

That upward trajectory began on a rainy day at Wembley 12 years ago.

At the start of the 21st century, the U’s had only recently been relegated from the second tier. By the end of the decade, they had fallen a further two divisions and dropped out of the Football League for the first time since 1962.

READ MORE: Looking back at Oxford United's last promotion six years on

As the 2010s dawned United were looking up under Chris Wilder, but they were four seasons into their stay in the Blue Square Premier.

For a long time, it looked like they could return to the Football League as champions but a run of seven points from eight games in the spring condemned them to the play-offs.

A 3-1 aggregate win over Rushden & Diamonds in the semi-final set up a meeting with York City in United’s first visit to Wembley since the 1986 Milk Cup final.

The club won their only major trophy that day, but legendary former manager Jim Smith – who was on the losing side as Queens Park Rangers boss – knew which game mattered more.

Speaking ahead of the play-off final, he said: “It is I think, without a shadow of a doubt, the biggest game in Oxford United’s history.”

Video: YouTube/OxfordUnitedTV

The 33,000 U’s fans comprised the majority of the crowd and they were in dreamland as their side went 2-0 up after 21 minutes.

Matt Green fired United ahead when he capitalised on York goalkeeper Michael Ingram going for a wander, before he teed up James Constable to plunder his 26th goal of the season.

But the mood changed when Ryan Clarke let an Alex Lawless corner slip through his gloves and over the line, setting up an unbearable second half.

York had chances to level and the U’s had opportunities to seal victory, but as the game entered stoppage-time there was still only one goal in it.

The Minstermen swung in another corner and this time United dealt with it, allowing Alfie Potter to race away with Sam Deering alongside him.

The substitutes combined as Potter fed Deering, who returned the favour to leave the 21-year-old one-on-one with the goalkeeper.

Potter took a touch, steadied himself and fired home in one of the great moments in United’s history.

They were a Football League club again - and not a moment too soon.

United: Clarke, Batt, Creighton, Wright, Tonkin, Bulman, Chapman (Day 87), Clist, Green (Potter 68), Constable, Midson (Deering 78).