League One Brentford pulled off the shock of the FA Cup fourth round with a 2-1 victory over Premiership strugglers Sunderland at Griffin Park.
Brentford had enjoyed the better of the first half but Sunderland appeared to be working their way back into the match after the interval only to be stunned by Dudley Campbell, who beat three players, jinked round goalkeeper Kelvin Davis and slotted home left-footed in the 57th minute.
However, Julio Arca equalised for the Black Cats nine minutes later and that appeared to have spared their blushes until Campbell snatched a winner in the 89th minute.
Colchester, conquerors of Premiership hopefuls Sheffield United in the last round, pulled off another surprise by beating another Championship side Derby 3-1 to reach the fifth round.
The League One high-fliers went ahead when Neil Danns' shot was deflected past Lee Camp.
Danns then fired in another deflected effort in the 52nd minute to put Colchester 2-0 up before Richard Garcia made the game safe on the hour ahead of Tommy Smith's 79th-minute consolation penalty.
A surprise was on the cards at Goodison Park where Everton came within 17 minutes of beating runaway Premiership leaders Chelsea.
James McFadden slipped in between John Terry and Asier Del Horno to head Nuno Valente's 36th-minute cross down past Carlo Cudicini but England midfielder Frank Lampard equalised for the visitors in the 73rd minute.
The game of the day was at Upton Park where, despite a number of floodlights failing in the second half, West Ham came out 4-2 winners against Premiership rivals Blackburn.
On-loan Arsenal forward David Bentley scored one of the fastest FA Cup goals to put Blackburn ahead after just 28 seconds, converting Shefki Kuqi's cross, but when Zurab Khizanishvili handled a cross Teddy Sheringham dinked a cheeky penalty straight down the middle for the equaliser.
Yossi Benayoun combined with Bobby Zamora to allow Matthew Etherington to put West Ham ahead in the 37th minute and Khizanishvili's 59th-minute own goal sealed Blackburn's fate.
Even though Lucas Neill pulled one back in the 65th minute Bobby Zamora rounded things off at 4-2.
Struggling top-flight side Birmingham were saved from defeat at Reading by substitute David Dunn's 67th-minute goal after Shane Long had put the Championship runaway leaders ahead in the 31st minute.
League Two Leyton Orient were denied a deserved replay as, despite coming back from a goal down, they were defeated 2-1 at Charlton, who scored a 90th-minute winner.
Jon Fortune headed in Darren Ambrose's seventh-minute cross but Lee Steele stabbed home in the 53rd minute after a good run by Joe Keith for the equaliser, only for Jay Bothroyd to provide a heartbreaking finish for the Os.
Graeme Souness' turbulent week ended in the best possible way as Newcastle edged past Cheltenham and into the FA Cup fifth round.
Goals from Michael Chopra and Scott Parker in quick succession just before half-time were enough to clinch victory and ease the pressure on the manager.
Middlesbrough were held to a 1-1 draw at Coventry despite taking the lead very early in the second half when defender Marcus Hall's sliced clearance allowed Jimmy Floyd Hasselbaink to score.
However, good work from Gary McSheffrey saw him cross for Stern John to volley home in the 54th minute.
Andy Cole scored the only goal of the game in the 84th minute as Manchester City moved into the fifth round with victory over Wigan.
Milan Baros scored two goals within four second-half minutes to help Aston Villa to a 3-1 victory at home to League One Port Vale.
Nathan Lowndes' 85th-minute goal briefly gave them hope before Stephen Davis' late strike finished them off.
A 90th-minute goal from Southampton's Kenwyne Jones was enough to see off managerless Leicester at the Walkers Stadium, while Stoke' were 2-1 winners at home to League One Walsall.
Mamady Sidibe scored on the stroke of half-time and Luke Chadwick added a second four minutes after the break before Walsall's Kevin James pulled one back in the 51st minute.
The all-Championship tie between Preston and Crystal Palace at Deepdale finished 1-1 after Eagles striker Andrew Johnson's eighth minute goal was cancelled out by Brian O'Neil's effort in the 27th minute.