A first half performance which had Ulster 19 points clear was entirely undone in a second 40 minutes as Richie Murphy’s men somehow lost their way and with it the game.
Cardiff scored 21 unanswered points to snatch this from an Ulster side who looked as if they had done enough to win after first half scores from Cormac Izuchukwu and two by Jude Postlethwaite.
Ulster were seemingly unable to do anything to puncture the Welsh side’s momentum, losing David McCann to a yellow card, and then just lost their way, Callum Sheedy’s 68th minute conversion killing the province’s hopes, though Nathan Doak fell just short with a last-gasp long range penalty shot.
So, Ulster have still to win away from home. No way for them to head into the November break. Horrible really.
Indeed, the importance of signing off in the right way until the end of next month had not been lost on anyone in the Ulster camp, particularly as they had come off two bonus point home victories with this game in the Welsh capital, on paper at least – Ulster having won on the previous six occasions the sides have met – looking as if it ought to have a promising conclusion for Richie Murphy’s squad.
An added incentive was not only the prospect of three straight wins from this initial block of games but also a first away win after the two rather tricky encounters in South Africa, the freshest memory of that two-game trip being the spanking handed to the province by the Springbok-heavy Bulls.
But, almost unbelievably – and with Iain Henderson an early depature too – it all unravelled just when it appeared that all Ulster had to do was bank their bonus point score.
The opening exchanges, rather worryingly for Ulster, saw the scrum under pressure from the off, an early penalty being conceded, though Cardiff were unable to make inroads into the visitors’ red zone from that initial source.
Cardiff’s initial game plan was to leather it in the air and force the error for a scrum but, after nine minutes, Werner Kok won a turnover off Cameron Winnett and Ulster kicked the penalty to the 22.
Their first incursion into the 22 turned into a five-minute stay, with tap-and-go penalties gradually drawing them closer and closer to scoring.
Evan Lloyd was binned on 12 minutes as Ulster cranked up the heat near the line and eventually the pressure told with Izuchukwu driving through, Doak converting on 14 minutes.
Three minutes later Ulster had their second try on the board, Doak beginning the move with a mazy run towards the left flank, linking up with Stuart McCloskey and then, from the recycle, Postlethwaite punctured the defence off an Iain Henderson assist.
Doak again converted and it was 14-0 with not even 20 minutes gone.
Try number three looked inevitable and came with McCloskey again out on the wing, getting the ball after Kok had kept it in play on the opposite side.
This time the Ireland centre chipped over the top and Postlethwaite collected to score his second, though Doak missed the extras.
At this stage it was all Ulster, though the sight of Henderson leaving the field on 24 minutes – on his first game back since suffering a concussion against Connacht – looked concerning not only for his involvement in this game but also, going forward, for Ireland in the November Tests.
The remainder of the half saw Cardiff create a few opportunities but they failed to make any headway and, though Ulster didn’t score again, they looked well in control as the half ended with them leading 19-0.
The home team now had to start the new half in a positive manner but, though they won a penalty from the restart after Postlethwaite was wrapped up and put it in the corner, Harry Sheridan – on for Henderson – got up to steal the ball and Ulster cleared.
But Cardiff came again, Ben Thomas’ line break and pass coming close to putting Grady away only for Mike Lowry’s half tackle to bring him down and, with the Wales winger hoping his momentum would take him to the line, Nick Timoney came from nowhere to knock him into touch.
More worrying signs then arrived for Ulster, McCann yellow carded for a cynical play in an offside position.
Now the Welsh had the bit between their teeth, the resulting lineout maul brought them yardage and the ball was spun right to left, Stephens spectacularly diving in at the corner, Calum Sheedy slotting an excellent conversion.
The home team then ought to have done better when Stephens’ pass to Grady ended up going forward after a Sheedy chip had caused mayhem for those in red.
Then, just after McCann came back on, Sheridan went on a rampaging run after some neat footwork from Doak, however the replacement lock was held up over the line just on the hour.
With the game really opening up, Cardiff were next to move the scoreboard, Daf Hughes cutting Ulster’s lead after he spun out of a maul with Sheedy again converting the 64th minute score.
They weren’t finished either and the game was turned on its head when another penalty was cornered and the Cardiff maul hit top gear with Thomas Young getting their third try to tie the scores.
Sheedy nailed the two points and Cardiff, once 19-0 behind now had the lead.
With five minutes left, Ulster won a penalty five metres inside their own half and Doak called for the tee. Though he struck it well, the ball fell just short.
Cardiff: C Winnett; M Grady, R Lee-Lo, B Thomas, I Stephens; C Sheedy, A Davies; E Byrne, E Lloyd, K Assiratti; J McNally, T Williams; B Donnell, D Thomas, A Lawrence.
Replacements: D Hughes (for D Thomas, 20-25mins, and for Lloyd, 51mins), C Domachowski (for Byrne, 52mins), R Litterick (for Assiratti, 50mins), R Thornton (for T Williams, 69mins), J Botham (for Donnell, 50mins), T Young (for D Thomas, 50mins), R Jennings (for B Thomas, 59mins).
Unused sub: J Mulder.
Yellow card: E Lloyd (12mins)
Ulster: E McIlroy; W Kok, J Postlethwaite, S McCloskey, M Lowry; A Morgan, N Doak; E O’Sullivan, J McCormick, T O’Toole; I Henderson, K Treadwell; C Izuchukwu, N Timoney, D McCann.
Replacements: J Andrew (for McCormick, 78mins), A Warwick (for O’Sullivan, 59mins), S Wilson (for O’Toole, 52mins), H Sheridan (for Henderson, 24mins), Marcus Rea (for Sheridan, 70mins), J Cooney (for Morgan, 69mins), B Carson (for McCloskey, 66mins).
Unused sub: B Moxham.
Yellow card: D McCann (47mins)
Referee: S Grove-White (SRU)
Relive all the action on our LIVE blog below!