Cardiff City supporters were handed the bragging rights in Wales after a Steven Caulker header was enough to earn Malky Mackay's side a hard fought 1-0 victory over bitter rivals Swansea City.
After a disappointing first half in which both sides struggled to create any clear cut chances, a towering header from the former Swansea City defender flew past a helpless Michel Vorm.
Swansea tried their best to get back in the game with Alejandro Pozuelo forcing a fine save from David Marshall just moments into injury time.
But after five minutes of injury time had been shown Swansea went down to ten men after Vorm took out Frasier Campbell who was racing through around 30 yards from goal.
It summed up a poor afternoon for Swansea who struggled throughout as Cardiff's summer signing Gary Medel produced an outstanding display in the middle of the park.
Despite the build-up and the promise of fireworks the game failed to take to life in the first half as both sides employed a cautious approach.
The first real chance of the game fell to Michu who was well picked out by Jonjo Shelvey. The Spain international connected well from 20 yards but it was straight at David Marshall.
Swansea were allowed plenty of possession as Cardiff simply sat off and allowed their Welsh counterparts to consistently pass the ball across midfield, though their was a distinct lack of incisiveness from Michael Laudrup's side.
Having seen Swansea enjoy most of the possession in the first 45, Cardiff came out fast as Peter Odenwingie earned an early corner which seemed to bring the home support to life.
The deadlock was finally broken after 62 minutes after some good work from Kevin Theophile-Catherine who chased a long ball to the byeline and was rewarded with a corner.
Former Swansea City loanee Caulker then soared above Chico Flores to power a header past Vorm and hand Cardiff the lead.
Swansea reacted by bringing on another striker in the form of Wilfried Bony and he almost made an immediate impact as he stabbed the ball just wide of Marshall's goal after good work from Jonathan de Guzman.
Cardiff refused to sit on their lead and substitute Frasier Campbell went close with less than ten minutes remaining as his first effort was blocked by Flores, before he got a second bite of the cherry but could not beat Vorm.
Pozuelo forced a fine save from Marshall late on before Campbell latched onto a long ball up field and headed the ball past Vorm. The Dutch keeper decided to impede the striker and was subsequently shown a red.
Having made all their substitutions Swansea were forced to put Angel Rangel in goal and the Spaniard was forced to instantly pull off a save from the resulting free kick.
Cardiff were able to see out the remaining few minutes to earn Mackay a memorable victory in the first ever top fight Welsh derby.