It was the biggest cheer of the day and it happened five minutes before kick-off. Two thousand Oxford fans, with an enormous flag and lots of ripped up Yellow Pages, celebrated wildly as their team ran on to the pitch.
United were starting their second stint as a Football League club.
It is difficult to put your finger on exactly why it feels so good being back in the League.
As a friend said before the match: "The last time we entered this division [after relegation in 2001] it felt like the lowest moment in the club's history. This time, it feels like the best".
There is the kudos of being a Football League team, or more to the point, not being a non-league team.
There are the financial benefits of TV deals, advertising and sponsorship.
There is the simple pleasure of being able to watch the goals on the BBC's Football League Show on Saturday night and even getting occasional coverage elsewhere in the media.
But the reason for the celebration was that for the first time in a long, long time, Oxford had managed to break off the shackles of being a "losing team".
Now we feel like a team on the up. It feels so good.
When Oxford were relegated to the Conference on that fateful and painful afternoon in 2006, the club were in a poor state.
The glory years of the mid-80s were not just a distant memory but also a millstone around the club's neck.
"We'll be too good for that division next year," we would misguidedly tell ourselves after each relegation, while dropping like a stone from the Championship to League One, then League Two and, almost inevitably, into the Conference.
Oxford United had become the ultimate losing team. Our fans not only got used to screwing things up but we started to expect it.
Burton Albion and Oxford battle it out at the weekend
The groans became louder each game, the tension on the terraces turned to anger and the atmosphere at matches became edgy, nasty and negative.
On the pitch, we were generally rubbish. Off it, we were worse.
We had done a Company Voluntary Agreement (CVA) long before they became fashionable (and points deductible).
We found ourselves in a situation where we did not own the (unfinished) ground we play in, paying rent and receiving nothing from all match-day catering.
It was hard to see how the club was going to recover from relegation from the League. Except, of course, we told ourselves we would bounce back straight away.
Here is an unusually frank passage from the Burton match-day programme:
"I remember Oxford arriving in non-league's top tier and believing like so many clubs before and since that they were too big for the division and that promotion was a divine right
"But the U's discovered it's a tough league to get out of and that it's progressive non-league teams who move up rather than ex-league teams hampered by debts and years of mismanagement."
Pretty much spot on.
We assumed big crowds and a team of players from the higher leagues would be more than enough to win us promotion. It took us two-and-a-half seasons to find a winning formula.
It involved a new chairman, Kelvin Thomas, who actually ran the club both as a business AND as a football club.
It took a manager, Chris Wilder, who understood that hunger and desire in players counted for more than CVs and agents.
It's been a long four years but we're moving in the right direction now
Oxford chairman Kelvin Thomas
Even then, we nearly threw away promotion last year. Eight points clear at the top in December, a mid-season wobble turned ugly.
That negativity reared its ugly head. Stevenage romped the league but thankfully we found our form just in time for the play-offs.
Wembley was glorious. Three great goals. Promotion.
But the most important legacy for the club was that a generation of fans who had grown up only knowing defeat, failure and misery, could finally associate the club with winning something.
What's more, the magic day was witnessed by well over 30,000 fans supporting Oxford.
At a very conservative estimate, 10,000 people will have been watching United for the first time that day and will have seen them win in style at the national stadium. I bet we won a few more regulars that day.
I had written most of this article on the train up to the Burton match. I had already pretty much scripted the answers I expected to the questions I was going to ask.
I expected the chairman and the manager to say the club had become stronger for its time out of the Football League.
It did not pan out that way. I journeyed back home aboard the Major Rewrite Express.
"What did the club learn from its time in the Conference?" I asked chairman Kelvin Thomas. "That we never want to go back," was his reply.
Wilder said the 0-0 draw with Burton was a fair result
"Was winning at Wembley and rebuilding the club a good trade-off for being relegated to the Conference?" "No. Not at all. It's been a long four years but we're moving in the right direction now."
"Do you think the four years in the Conference did this club some good?" I asked manager Chris Wilder. "Listen, you are where you are," he replied.
He did not bite either. The rest of the answer was all about looking forward, taking the club on, aiming for, but certainly not expecting, immediate promotions.
From what you can tell from an opening-day fixture, Oxford look in good shape to mount a decent challenge this season.
The game itself was OK by 0-0 League Two standards.
Burton probably had the game's best two chances, while Oxford had more of the possession.
But with star striker James Constable losing his tussle with wily old Darren Moore, goal opportunities were few and far between.
Wilder was happy and said he was going to have a drink with Burton manager Paul Peschisolido. "Not many managers ever asked me for a drink in the Conference," he laughed.
Another reason to be pleased to be back in the League.
Dan Curtis is a producer for BBC Sport and an Oxford fan of many years. He used to edit Yellow Fever, an Oxford United fanzine.
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