Swansea City booked their place in the Capital One Cup last four after a 1-0 win over Middlesbrough at the Liberty Stadium.
The only goal of the game came with nine minutes remaining as Seb Hines headed a Jonathan De Guzman corner past Jason Steele and into his own net.
It put Swansea into the last four of the competition for the first time in their history alongside Bradford - memorable conquerors of Arsenal on Tuesday night - and Aston Villa, while Chelsea meet Leeds in the remaining quarter-final clash next week.
Middlesbrough gave as good as they got for most of a low-key contest in front of a 15,000 crowd, as both sides lacked a sharp attacking edge and laboured for long periods.
Grant Leadbitter went close for Boro, League Cup winners eight years ago, with a 21st-minute effort that forced Swans goalkeeper Gerhard Tremmel into a save low at his right post.
Tremmel was then forced to react smartly to keep out a Leadbitter effort, and Boro boss Tony Mowbray was the far happier manager at half-time in a tie that never seriously threatened to move out of second gear.
It was no surprise when Michael Laudrup made his first change just 10 minutes after the break when he sent on Luke Moore to replace Itay Shechter. Moore was immediately in the action, challenging Boro defender Andre Bikey just outside the visitors' penalty area that ended with both players going down.
Bikey required treatment before he could continue, but even though he attempted to run off his injury, it was to no avail. Faris Haroun also departed for Boro, with Andy Halliday and Richard Smallwood going on.
Laudrup also made a second switch, with Ki Sung-yueng going on for Wayne Routledge, but there was still no sign of the deadlock being broken.
Swansea, though, started to string some attacking phases together, and they went agonisingly close 15 minutes from time after Nicky Bailey was cautioned for bringing down Nathan Dyer. De Guzman took the resulting free-kick, and Steele palmed it on to the crossbar, keeping Boro level, although pressure continued to mount with Michu a consistent threat.
Referee Lee Probert then waved away Swansea claims for a penalty when Hines challenged Ki, and a game that had previously lacked an attacking flow suddenly opened up.
Boro could only survive such sustained pressure for so long, and the unfortunate Hines diverted the ball beyond Steele from a corner under pressure from Garry Monk as Swansea went ahead to ultimately secure a last-four place.
The sanction is one of a number of proposals being discussed by the game's ruling bodies, but has yet to be agreed by the Football Association.
Chelsea skipper John Terry was given a four-match ban for racially abusing QPR defender Anton Ferdinand, while Liverpool's Luis Suarez received an eight-match suspension for his abuse of Patrice Evra.
The PFA said on their official Twitter feed: "The PFA have agreed proposals with @FA that 'racist abuse' should carry a minimum five-match ban."
PFA chief executive Gordon Taylor said: "We are not opposed to it. We want there to be some consistency and to illustrate the seriousness of our approach to this issue."
The PFA also want all players and managers coming to England from overseas to have "cultural lessons" to make them aware of rules on discrimination under proposals to tackle racism. Until now only apprentices have been given such courses.
Meanwhile, FA independent director Heather Rabbatts insists the game must to respond to damning criticism of the handling of the Terry and Suarez cases.
Kick It Out chairman Lord Herman Ouseley has claimed there is "very little morality" at the top clubs, a lack of leadership and "a moral vacuum" in the game.
Rabbatts, appointed as an independent board member earlier this year and a potential candidate to be the next FA chairman, said Ouseley had raised important issues.
She said: "The issues that Herman Ouseley is raising are hugely important issues for the whole game and it has to respond to these challenges.
"There are a number of members from different parts of the game being consulted and we all have to rise to the current challenge.
"Despite the huge progress that has been made in tackling discrimination there is a need for renewed energy."
The midfielder has not featured for the Royals since the 1-0 defeat at Liverpool in October, and is believed to have reprimanded by the club for not making the trip to the Stadium of Light.
The Royals crashed to a 3-0 defeat on Wearside, their fourth loss on the bounce which leaves them 19th in the table and six points off safety.
Royals boss Brian McDermott confirmed afterwards that Guthrie had refused to travel and is planning on holding talks with the 25-year-old.
"He made a decision that his head wasn't right to travel," McDermott said.
"Everyone has got to be going in the same direction, that's really, really important for me as a group, and we have had that for a period of time.
"You have to put yourself up to be selected in each and every game, and that means every player.
"Any player has to be part of what we are about. We can't deviate from what we have been about over the last three years.
"We are very much about the group - we have to be. We all have to pull in the same direction. It's probably not a conversation for this evening, but it's something that we need to address in the week."
