Kemar Roofe scored a double as League Two Oxford United pulled off the biggest shock of the FA Cup third round so far by beating Premier League Swansea City 3-2 on Sunday.
The Welsh side took the lead in manager Alan Curtis' first game since being given the job until the end of the season as Jefferson Montero finished off a wonderful flowing move involving Marvin Emnes in the 23rd minute.
But Oxford, who are third in League Two, produced a magnificent comeback to progress to the fourth round.
Liam Sercombe levelled matters just short of half-time from the penalty spot, before striker Roofe - linked with a move to Newcastle United - hit home from the edge of the area in the 49th minute.
Roofe then converted at the end of a quick break 10 minutes later to make it 3-1, only for Bafetimbi Gomis to halve the deficit and fray the nerves of the home fans at the Kassam Stadium.
Gomis' 66th minute strike at least gave Swansea hope of salvaging a replay, but Oxford held out to seal a famous victory.
Oxford started brightly and would have taken the lead if not for a fine save from Kristoffer Nordfeldt, who acrobatically turned Ryan Taylor's header from Christopher Maguire's left-wing cross over.
But the fourth-tier side soon fell behind courtesy of a stunning piece of link-up play between Montero and Emnes.
Montero drifted in from the left before laying the ball off for Emnes, who smartly flicked the ball back for the Ecuador international to find the bottom-left corner with a stylish finish.
Swansea could have been further ahead had Jonjo Shelvey been more clinical, the midfielder volleying over from a failed clearance and then sending a free-kick into the side-netting.
Oxford refused to lie down and levelled in first-half stoppage time following an ill-advised challenge by Bartley.
Nordfeldt did well to deny Jake Wright but, from the rebound, Bartley lunged in on Alex MacDonald and, despite not appearing to make a great deal of contact, was punished by referee Kevin Friend.
Sercombe stepped up and lashed the ball down the middle from 12 yards for his 14th goal of the season and Oxford completed the turnaround four minutes into the second half.
Roofe cut onto his right foot and curled towards goal, with the previously impressive Nordfeldt allowing the shot to creep into the bottom-right corner.
Sam Slocombe tipped over a Jack Cork header to deny Swansea an equaliser and, from the subsequent corner, Oxford gave themselves breathing room with a rapid counter-attack.
The ball broke to Maguire after the corner was cleared and the winger squared the ball for Roofe, who raced through on goal and saw his shot loop into the net despite a heavy touch from Nordfeldt.
However, Gomis cut the gap seven minutes later, the Frenchman slotting home after being played in by Cork, although replays indicated he may have been marginally offside.
Montero was thwarted by Slocombe in what served as the best chance to level for Swansea, who must now focus fully on their fight against relegation from the top flight.