Sunderland will join Manchester City in the semi-finals of the League Cup after overcoming Chelsea in a thrilling 2-1 victory at the Stadium of Light.
Ki Sung-Yueng's extra-time goal produced the upset of the night as the Black Cats stole an unexpected victory from the favourites.
All three goals were scored by Gus Poyet's side with Chelsea unexpectedly going ahead early into the second half when Lee Cattermole inadvertently prodded the ball into his own net.
Despite Chelsea's dominance in normal time the only real chance fell to Samuel Eto'o but his one-on-one with Vito Mannone saw him send his shot wide.
On the night it was Sunderland who came up with the goods following a late goal from Fabio Borini to take the game into extra time before super-sub Ki won them the tie with a 117th-minute strike.
Chelsea boss Jose Mourinho was left puzzled by the outcome in light of his team's dominant performance.
"I think they played very well," he said.
"It is the same story of Stoke, of Everton, of every match we lost. We never lost a match because the opponent is stronger than us.
"We don't kill the opponent, we give them life. It's always the same."
Meanwhile City striker Edin Dzeko scored twice in the second quarter-final on Tuesday at the King Power Stadium to help his side ease comfortably through to the final in impressive fashion with a 3-1 victory over Championship side Leicester City.
Left-back Aleksandar Kolarov scored the opener via a stunning 25-yard free-kick before James Milner set Dzeko up twice as City extended their advantage.
Lloyd Dyer scored a late consolation for Nigel Pearson's side but the Foxes were unable to stage a recovery.
The home side otherwise had very little in the way of chances as Manuel Pellegrini's side worked hard to ensure that goalkeeper Joe Hart enjoyed a quiet game while at the other end Milner and Jesus Navas kept Leicester stopper Kasper Schmeichel constantly on his toes.
"They were probably too good for us. Looking at the first goal, it was a great strike, but the second and third goals were disappointing from our perspective," said Pearson.
"When you play against sides as good as Man City you have to give yourself the best chance. We got punished for small mistakes."
Pellegrini's side join Sunderland in the hat for the League Cup semi-final draw and will be joined by either Stoke City or Manchester United and Tottenham Hotspur or West Ham United in the last four.
"It is an important competition," the Chilean said.
"It is important to win every game you play in and to get to the final at Wembley would be wonderful for the supporters."