The English top flight will experience the fire and fury of a Welsh derby for the first time on Sunday when Cardiff City host Swansea City in the Premier League.
Cardiff's promotion from the Championship in May means that there are now two teams from Wales doing battle among the English elite and passions are expected to run high at the Cardiff City Stadium.
Swansea are becoming an established Premier League force, finishing 11th and ninth since being promoted in 2011 and winning last season's League Cup, but they will be overtaken by Cardiff if they lose on Sunday.
Located 42 miles apart on the south Wales coast, the two teams are fierce rivals and their head-to-head encounters tend to be tempestuous affairs.
Old wounds were reopened this week when it was revealed that referee Mike Dean will officiate the game, four years after he was struck on the forehead by a coin thrown from the stands during the same fixture.
Cardiff manager Malky Mackay said he had no concerns about Dean's appointment, describing him as a "very good referee", but he admits that the game has a singular context.
"It's not just another game and I would be lying if I said that," he said.
"I know the passion of our fans and what the atmosphere in our stadium is like, but I don't think it is going to touch the sides of what we will feel on Sunday. It will be an incredible atmosphere when the players walk out.
"I think it is something all our fans have looked forward to since we were promoted and it does hold that extra special edge."
Mackay has endured a difficult few weeks, having seen his trusted head of recruitment Iain Moody dismissed and replaced by a 23-year-old Kazakh, Alisher Apsalyamov, with no known experience in professional football.
Reports in the British media claim Apsalyamov has been asked to step down while the government investigates his visa situation, but Swansea manager Michael Laudrup has downplayed the significance of the off-pitch upheaval.
"I don't think I am the one capable of answering what is happening off the pitch at Cardiff," said the Dane.
"There can be a lot of things going on, but for the game you park everything and play the game to try and win, which is much more important than what happens off the pitch."
Laudrup's preparations have been aided by the return to fitness of captain Ashley Williams, who played for 90 minutes in last weekend's 0-0 draw with West Ham United following a spell out with an ankle ligament problem.
Cardiff have won just one of their last seven league games and sit only a point above the relegation zone, but Mackay has no new injury problems to contend with.
Williams and Cardiff veteran Craig Bellamy are likely to be two of only three Welsh players to start the match -- alongside Cardiff left-back Neil Taylor -- but Laudrup says the game's significance will not be lost on his foreign contingent.
"You cannot ask a guy from Spain to understand it completely, but they have their own derbies," he said.
"We have players who played in Sevilla v Real Betis, which is a huge derby in Spain.
"When they hear the word 'derby', they know what it means; perhaps not exactly what it is here, but wherever you are around the world there is always one thing in common: the importance to the fans."
Swansea have become renowned for the quality of their football in recent seasons, but Cardiff have historically enjoyed greater success than their rivals, winning the 1927 FA Cup and finishing second in the league in 1924.
Sunday's game will also represent the first time that Cardiff play Swansea since Malaysian owner Vincent Tan controversially changed their colours from blue to red in 2012.