Nottingham Forest, struggling at the wrong end of the Championship (second division), scored the upset of the day when they crushed Premier League Manchester City 3-0 in the FA Cup third round on Saturday.
Goals from Nathan Tyson, Robert Earnshaw and Joe Garner sent City, regarded as the world's richest club after their summer takeover by oil-rich Arab billionaires, crashing to a humiliating defeat.
City were one of four Premier League teams to be knocked out of the Cup with Stoke City humbled 2-0 at League One (third division) Hartlepool United and Bolton Wanderers and Wigan Athletic losing all-Premier League ties.
Five other Premier League clubs will be involved in replays including Cup holders Portsmouth, and Chelsea.
Manchester United, who have won the FA Cup a record 11 times, and Aston Villa will be in action on Sunday while Blackburn Rovers face minor league Blyth Spartans on Monday.
Four other matches, including the Midlands derby between Birmingham City and Wolverhampton Wanderers will be re-arranged after being postponed on Saturday.
Forest's stunning upset at Eastlands was the perfect tonic for new manager Billy Davies who takes over officially on Monday. Caretaker John Pemberton took charge of Forest for the last time following the dismissal of former coach Colin Calderwood just before Christmas.
"It was dream stuff," Pemberton told BBC Radio. "You have to give the players a massive amount of credit for today's game. They were absolutely unbelievable. We turned out 3-0 winners and we deserved it in the end."
League One Hartlepool also caused a major shock when they beat Premier League Stoke 2-0 at Victoria Park to reach the fourth round for only the sixth time.
Hartlepool went ahead early in the second half when Michael Nelson scored with a header before David Foley made it 2-0 with a 30-metre strike in the 76th minute.
Stoke manager Tony Pulis, who rested seven first team regulars, told BBC Radio: "As soon as the first goal went in, Hartlepool were the better team. I am obviously desperately disappointed."
Hartlepool's caretaker boss Chris Turner told BBC Radio: "I've had a lot of personal disappointments in the FA Cup and a lot of personal disappointments as a manager, but I must say that in all my career, whatever I have done, today is the best day of my life in football."
Southend United, also in League One, had an afternoon to remember by forcing a 1-1 draw at Chelsea with Peter Clarke heading the equaliser at Stamford Bridge in stoppage time on his 27th birthday.
Salomon Kalou had put Chelsea, who dominated almost the entire match, ahead after 31 minutes but they were punished for failing to score a second.
FA Cup holders Portsmouth dominated for long periods against Championship side Bristol City who forced a replay back at Ashton Gate after a goalless draw at Fratton Park.
Premier League West Bromwich Albion were also held to a 1-1 draw by Peterborough United, the League One side managed by Manchester United manager Alex Ferguson's son Darren.
There were no such problems for Arsenal who beat Championship Plymouth Argyle 3-1 or the other Premier League teams playing against lower league opposition.
Premier League leaders Liverpool won 2-0 at Championship side Preston North End, Everton won 1-0 at League Two Macclesfield Town, while two goals from Andy Johnson gave Fulham a 2-1 win at Championship side Sheffield Wednesday.
West Ham United had an easier afternoon beating last season's beaten semi-finalists Barnsley 3-0, while Middlesbrough also made it to the last 32 with a 2-1 win over minor league Barrow with Afonso Alves scoring both their goals.