An inspired move by manager Ian Atkins in starting with raw recruit Jefferson Louis earned Oxford United a plum tie against Arsenal at Highbury in the third round of the FA Cup.
Louis rewarded Atkins with the only goal against local rivals Swindon Town at the Kassam Stadium and it is the first time in 15 years that Swindon have not reached the third round.
It also denied the Nationwide Division Two club their third win on the bounce and levels their encounters with Swindon to five wins each and one match drawn.
Louis, who converted the vital penalty against Charlton Athletic in the Worthington Cup earlier this season, struck after 65 minutes when he soared above the Swindon defence to head in a long throw by Scott McNiven.
Thirteen minutes earlier he set up Steve Basham with an opening in front of goal but his close-range shot was blocked.
Swindon shaded the first half and should have led at the interval.
Danny Invincibile wasted a good chance in the seventh minute heading over from a right-wing cross and 30 minutes later Alan Reeves headed a cross wide from close in.
Their worst miss though was by Invincibile in the 45th minute. He was well-placed but his drive went across goal and out for a throw-in.
Invincibile offered the main threat with a surging run past three defenders in the 59th minute but he spoilt it with a shot high over the bar from the edge of the penalty area.
A delighted Atkins said after the game: "I thought we deserved the win. Everyone in the team was brilliant but Jefferson Louis was awesome.
"We lost our way a little in the first half but we got it back, and to face Arsenal in the next round is a massive boost to the club. I may now be able to get a centre half that we need." Swindon manager Andy King was disappointed with the way the winning goal went in.
"Our big centre-half should have won the ball and it was a lucky goal. It is going to be a rich one for Oxford.
"I don't think that we were awful and I didn't think we were good."