London: Chelsea, Manchester United and Manchester City reached the FA Cup fourth round on Sunday, but third-tier Sheffield United confirmed their cup pedigree by winning 3-0 at Queens Park Rangers.
Nigel Clough`s League One side, who reached last season`s semi-finals and face Tottenham Hotspur in the last four of this season`s League Cup, won via a Marc McNulty goal and a second-half brace from Jamal Campbell-Ryce.
QPR, whose manager, Harry Redknapp, made seven changes to his starting XI, became the second top-flight team to be knocked out in the third round following Newcastle United`s 1-0 loss at Leicester City on Saturday.
"We know we can come and compete with top teams," said Sheffield United first-team coach Chris Morgan.
"It`s great to have a run in the cup -- great for supporters and for the revenue of the club."
Premier League joint-leaders Manchester City were given a scare by second-tier Sheffield Wednesday before coming through 2-1 at the Etihad Stadium thanks to a 91st-minute winner from James Milner.
Wednesday had lost 7-0 at City in the League Cup in September, but they took a 14th-minute lead through Atdhe Nuhiu, only for Milner, on his 29th birthday, to equalise in the 66th minute before snatching a last-gasp winner.
City`s cross-town rivals Manchester United also recorded a hard-fought victory over lower-league opposition, winning 2-0 at third-tier Yeovil Town.
United manager Louis van Gaal named a strong side featuring Wayne Rooney and Radamel Falcao for his first FA Cup tie, but had to wait until the 64th minute for Ander Herrera to put the visitors in front with a looping 20-yard shot.
Yeovil continued to press, but United killed the game off in the last minute when Rooney freed substitute Angel di Maria to run through and chip home.
"I had expected this," Van Gaal told the BBC. "It is always difficult to play against a team like this, who play long balls. You have to fight and they gave us a lot of pressure."Chelsea enjoyed a rather more straightforward victory, winning 3-0 at home to second-division Watford courtesy of second-half strikes by Willian, Loic Remy and Kurt Zouma.
It could prove a positive omen for Jose Mourinho`s side, as Chelsea beat Watford en route to glory in the competition in 1970, 2009 and 2010.
Southampton were taken to a replay by Championship side Ipswich Town after a 1-1 draw at St Mary`s, while it took a stunning late strike by Christian Benteke for Aston Villa to overcome second-tier Blackpool 1-0.
Meanwhile, non-league Wrexham of the fifth-tier Football Conference came within 10 minutes of creating another piece of FA Cup history, only to lose 3-1 at top-flight Stoke City.
The Welsh side, who knocked out holders Arsenal in the third round in January 1992, went 1-0 up in the 73rd minute at the Britannia Stadium when Mark Carrington headed home a right-wing cross from Connor Jennings.
But with another famous upset beckoning, Marko Arnautovic stabbed home an equaliser in the 80th minute before Stephen Ireland claimed a late brace to send Mark Hughes`s side through.
Alan Pardew made a winning start to life as manager of Crystal Palace, who won 4-0 at non-league Dover Athletic thanks to a first-half double by centre-back Scott Dann and goals from Dwight Gayle and Kevin Doyle.
Pardew was appointed Palace manager on Saturday after leaving Newcastle.
Meanwhile, Sunderland repeated their victory over Leeds United in the 1973 final with an identical 1-0 win against the Championship club at the Stadium of Light.
Sunderland, whose 1973 win was one of the biggest upsets in the competition`s history, prevailed courtesy of a drilled 33rd-minute effort by Dutch left-back Patrick van Aanholt.
Holders Arsenal enter the competition later on Sunday when they host Hull City in a repeat of last season`s final, which Arsene Wenger`s side won 3-2.
Tottenham travel to Burnley on Monday in a repeat of the 1962 final, which Spurs won, and Liverpool visit third-tier AFC Wimbledon for a tie that recalls the original Wimbledon`s shock victory in the 1988 final.