Everton skipper Phil Neville fired his side into the fifth round of the FA Cup as the Toffees gained a small measure of revenge for their 2009 final defeat to Chelsea.
Boss David Moyes' side were just 75 seconds away from being dumped out of the competition when Leighton Baines struck a stunning free-kick in the 119th minute to send the fourth-round replay with the Blues into a penalty shoot-out.
Following a goalless 90 minutes at Stamford Bridge in which Chelsea wasted a number of chances, Frank Lampard finally fired his team in front in the 104th minute.
Aiming for a third successive FA Cup success, Chelsea seemed set for a last-16 date with Reading until full-back Baines delivered his stunning blow to lift the visitors' spirits at the death.
Remarkably Baines then had Everton's first penalty in the shoot-out saved by Petr Cech as Chelsea took a 2-0 lead courtesy of Lampard and Didier Drogba.
But first Nicolas Anelka was denied by Tim Howard before Ashley Cole blazed high and wide, affording Neville the opportunity to step up and duly make himself the hero.
At the Britannia Stadium and St Andrew's, Stoke and Birmingham both enjoyed routine passages into the last eight, winning 3-0 against npower League One opposition in Brighton and Sheffield Wednesday respectively.
Stoke manager Tony Pulis' side, through to the sixth round for the second successive year, scored all their goals in a one-sided first half from which there was no way back for League One leaders Albion.
Goalkeeper Peter Brezovan was at fault for the first two goals in the 14th and 22nd minutes, allowing John Carew and Jon Walters to put the home side in control before Ryan Shawcross inflicted more misery on the visitors in the 43rd minute.
Wednesday's hopes were also crushed early on as Jean Beausejour and Obafemi Martins gave the Blues a 2-0 lead inside 17 minutes, the latter scoring his first goal since joining the club on loan last month from Rubin Kazan.
David Murphy then added a third in the 53rd minute to send Alex McLeish's into the sixth round for the first time since 2006.
Remarkably, it was not so easy for Manchester United in their fifth-round clash with non-league Crawley, who gave Sir Alex Ferguson's side quite a fright at Old Trafford.
Despite Ferguson making 10 changes, undoubtedly fielding a weakened side ahead of four away matches in the next two weeks that includes trips to Marseille, Chelsea and Liverpool, many would still have fancied a cricket score.
Instead, United scraped through to the last eight on the back of nothing more than a glancing 28th-minute header from Wes Brown as Blue Square Bet Premier side Crawley came within inches of causing one of the greatest upsets in cup football.
In the second minute of injury time, substitute Richard Brodie saw a header bounce on top of the crossbar, and with it went Crawley's last hope of a fairytale ending.