Sunderland came back from the brink of defeat to stun Chelsea in extra time and claim a place in the semifinals of the Capital One Cup. The home side were heading to defeat at the Stadium of Light after Lee Cattermole’s own goal had put Chelsea in front in the first minute of the second half. But with Chelsea not doing enough to put the tie to bed, Fabio Borini struck a dramatic equalizer with two minutes of normal time remaining. Substitute Ki Sung-Yueng then grabbed a winner similarly late in extra time.

While Sunderland’s priorities undoubtedly lie in trying to lift themselves from the foot of the Premier League table and to safety, Gustavo Poyet will no doubt he hoping that this win against his former club can provide a much-needed injection of belief into his side. By the end, it was hard to argue that Sunderland were not deserving of their win. Making it even sweeter is that it was a victory achieved against a strong Chelsea side, featuring the likes of Frank Lampard John Mikel Obi, Ashley Cole and the returning Gary Cahill alongside David Luiz at the back.

That will make the defeat even more difficult for Jose Mourinho to swallow. It was lifting the League Cup that kick-started his successful first spell as Chelsea boss, but it will not now provide similar impetus this time around. On current evidence, both he and his team could do with a spark. While Chelsea lie only two points off the top of the Premier League, this defeat was the continuation of poor performances that have so far marked the early stages of Mourinho’s second stint in charge at Stamford Bridge. While they have often got away their disappointing displays, as they did at the weekend against Crystal Palace, they were punished here.

Indeed, Chelsea had been somewhat fortunate to emerge with the three points when the sides met in the same arena just two weeks earlier. From early on, a repeat of that seven-goal thriller didn’t look on the cards.

There was little entertainment of any sort in the opening half. Andre Schurrle fired across goal, while Willian also struck an effort off target after an error from the otherwise excellent Wes Brown. But that was the closest that the game came to an opening goal in the first 45 minutes. Both sides struggled to maintain any quality possession, with a succession of speculative efforts hit wildly off target.

With Mourinho likely to have had some strong words at the interval, Chelsea came out for the second half and instantly got in front. The ever-positive Cesar Azpilicueta got forward from his natural right-back berth and put in a low cross right into the zone between goalkeeper and defenders and, in trying to prevent Frank Lampard from turning the ball in, Cattermole couldn’t prevent the ball from crossing the line with his knee appearing to get the final touch.

Chelsea had the chances to sew the game up too. Samuel Eto’o undoubtedly had the best of them after getting through on goal following an error from Craig Gardner, but the Cameroonian summed up the woes of Chelsea’s strikers by placing a shot the wrong side of the post.

Kevin de Bruyne and Andre Schurrle also went close as Chelsea controlled the second period against a Sunderland side that looked resigned to defeat. Instead, the home side made Chelsea pay for failing to make their superiority count.

Jozy Altidore appeared to have spurned Sunderland’s golden chance when he dallied in front of goal before seeing his shot blocked by Mark Schwarzer, but substitute Borini was on hand to tuck the ball in from a tight angle.

Suddenly in extra time, the match finally came to life. Chelsea threatened through David Luiz and Demba Ba but it was increasingly Sunderland that were looking likeliest to get a winner. Borini missed a glorious chance to get a second goal against his former club, while Michael Essien blocked a close-range effort from Altidore and Ki saw a header tipped over. From the resulting corner, though, the man on loan from Swansea struck the decisive blow.

Chelsea were left all over the place defensively from a deep cross to allow Borini to first hold the ball up before laying it off to his left for Ki, who had the time to take a touch and drill the ball low inside the near post.

The celebrations were wild and the euphoria should mitigate any tiredness in the legs ahead of the return to league action. For Chelsea, the extra 30 minutes are even more unwelcome in defeat, with their hectic schedule continuing with a vital top-of-the-table clash against Arsenal up next.

All Goals - Sunderland 2-1 Chelsea - 17-12-2013... by all-goals