Kevin Nolan reminded West Ham fans just how valuable he is to their promotion push with the opening goal of a scrappy game in south Wales.
Nolan, who returned from a three-match ban at the Cardiff City Stadium, coolly slotted past David Marshall in the Cardiff goal two minutes before half-time to hand the visiting Hammers an advantage they never surrendered.
It was a rare moment of quality in a match that lacked the fervour and intensity of the home side's previous outing in the Carling Cup final defeat to Liverpool seven days ago.
In fact, after a bright start, the after-effects of that memorable evening at Wembley seemed to tell in Cardiff's display.
They began the second half sluggishly and were fortunate not to find themselves three down inside an hour after Marshall saved well from Nicky Maynard and Mark Hudson backtracked to prevent Ricardo Vaz Te from tapping in.
The Bluebirds briefly looked like staging a comeback as Peter Whittingham struck the inside of a post from a free-kick.
But they were finished off in the 77th minute with George McCartney beating Marshall from a tight angle.
Cardiff manager Malky Mackay made one change to the side which so valiantly took Liverpool to penalties, with goalkeeper Tom Heaton dropping to the bench to make way for Marshall.
The Hammers were boosted by Nolan's return, while Henri Lansbury came into the side for Julien Faubert.
The hosts started the game well and Kenny Miller went within a whisker of firing a 20-yard effort into the bottom corner after 13 minutes.
For all Cardiff's early possession, however, West Ham should have taken the lead midway through the first half.
Lansbury crossed from the right, Jack Collison nodded the ball across goal and Maynard lashed over.
Aron Gunnarsson's 25-yard drive skidded past the left-hand post before the visitors sneaked into the lead on the stroke of half-time.
Cardiff dallied on the edge of their own area and Maynard capitalised to feed Nolan, who opened his body up beautifully to curl a sidefooted effort around Marshall.
West Ham could have made it two after 52 minutes when Nolan won possession in midfield and fed Maynard, but after hesitating in the box he poked the ball narrowly wide.
It was a worrying passage of play for Cardiff and Kevin McNaughton cut a relieved figure when his headed back-pass gifted Maynard a free shot on goal, only for Marshall to get down well to deny the ex-Bristol City striker.
Cardiff were rocking, but out of nowhere they almost got themselves back on level terms.
Gunnarsson's long throw picked out Hudson, but the City skipper could only head over the bar.
The Bluebirds went even closer five minutes later as Whittingham curled a delightful free-kick onto the left-hand post with Robert Green beaten.
However, with 13 minutes left, the Hammers put themselves out of sight.
McCartney broke down the left and when his cross was not properly cleared by the Cardiff defence, he fired the rebound beyond Marshall from an acute angle.
Miller struck the bar from a close-range header in stoppage time, but the game was gone for the home side.