Stant brought the tie level after 16 minutes with a diving header from Tony Rigby's cross and, after Mark Carter's angled drive put them ahead on aggregate after 31 minutes, the Third Division side were never headed.
Sheffield United's manager, Dave Bassett, roundly condemned his side. "I would say that the first half ranks as probably the worst Sheffield United performance since I've been here and possibly in the history of the club," he said.
A goal in the 16th minute of extra time by Jim Gannon gave Second Division Stockport County a 2-1 victory at Ipswich, which saw them past the First Division side 3-2 on aggregate. Stockport had looked on their way out to Claus Thomsen's first-half goal until Alun Armstrong levelled the tie with eight minutes of normal time remaining.
Charlton and Wimbledon, who shared nine goals in their first leg at Selhurst Park, kept the drama going right through to extra time at The Valley before the First Division side won 8-7 on aggregate. In the 97th minute, John Robinson, who is transfer-listed and on a weekly contract, finally scored the goal that earned Charlton a 3-3 draw on the night and a rare success over a team from a higher division.
Kevin Gallen, called up at the last minute when Trevor Sinclair withdrew with a domestic problem, put Queen's Park Rangers into the third round with an extra-time goal that finally put paid to Second Division Oxford United at Loftus Road.Reuse content