Ki Sung-Yeung scored a dramatic late winner for Sunderland to send Chelsea crashing out of the League Cup with barely two minutes remaining of extra-time in this compelling quarter-final.
Ki was booked for his role in the wild celebrations that followed his goal but that will hardly concern the on-loan midfielder. Sunderland had been outplayed for long periods and were lucky that Fabio Borini struck an equaliser in the 88th minute.
The Italian had come off the bench to cancel out Lee Cattermole's own goal at the Stadium of Light. On a night of several heart-stopping moments, it too would have been difficult to watch for some fans.
Cattermole had pushed the ball over the line under pressure from Frank Lampard -- who could have argued that the goal was his, but referee Anthony Taylor waited several moments for goal-decision technology to confirm the decision. Gus Poyet's men scarcely deserved it.
Jose Mourinho made eight changes to his side, but they appeared more than comfortable as they strolled their way through the opening minutes.
Sunderland goalkeeper Vito Mannone did well to gather an awkward shot from Willian before Andre Schurrle lifted a free-kick over the bar and Lampard missed from distance.
Chelsea's defensive vulnerabilities that were brutally exposed in the 3-2 defeat at Stoke threatened to surface again as the visitors laboured to clear Seb Larsson's crossed free-kick, with David Luiz blocking from Emanuele Giaccherini.
Sunderland steadied themselves and Jozy Altidore increasingly irritated the Chelsea defenders. Another deep free-kick from Larsson had just too much on it. Giaccherini could not then get on the end of a well crafted Craig Gardner pass.
The hosts also had a penalty appeal turned down after Andrea Dossena's cross hit the arm of Chelsea right-back Cesar Azpilicueta in the area. Wes Brown again gave the ball away to Azpilicueta. The defender was then fortunate not to concede a free-kick for his clumsy challenge on Samuel Eto'o on the edge of the area.
Schurrle also scuffed wide but the German soon gave the ball away at the other end. Adam Johnson's swaggering run took him past Lampard and into the area only for Gary Cahill to make an impressive clearance.
The visitors finally took the lead 38 seconds into the second half.
Kevin De Bruyne put Azpilicueta in behind the Sunderland defence and the Spaniard drove a cross over from the right, with Lampard sliding in with Cattermole as the ball crossed the line by about a yard. After the slight delay, Taylor indicated that technology had helped him to award the goal.
Eto'o dragged wide, then struck a shot that looped up off John O'Shea and wide. Mannone pushed away a fine effort from De Bruyne and Lampard missed twice from more than 20 yards as Chelsea searched for a second.
Sunderland were ragged but with two minutes remaining, Mark Schwarzer blocked from Altidore and Borini fired the ball into the far corner to force extra-time. Cue Ki's cameo. (© Daily Telegraph, London)