Cardiff took a giant step towards qualification for the knockout stages of the Challenge Cup as they came from behind to claim a bonus point victory over their Parisian opponents at the Arms Park.
They trailed 13-7 late in the first half, but then second row Rory Thornton and prop Keiron Assiratti forced their way over either side of the break to add to Tom Bowen’s sparkling early effort.
That quickfire double put the hosts in front and they sealed their win through the boot of fly-half Callum Sheedy and a late try from Player of the Match Ben Thomas.
Cardiff will be certain of a place in the last 16 if Ulster beat the Cheetahs in the Netherlands tomorrow and they will complete their Pool 3 programme on Sunday, January 18 when they travel to Sandy Park to take on Exeter.
Going into the clash with French club Racing, they showed eight changes from the side beaten by the Ospreys at Bridgend’s Brewery Field on New Year’s Day.
Flanker Taine Basham, South African centre Cornel Smit, full-back Jacob Beetham and wings Bowen and Iwan Stephens were among the players to come into the starting line-up.
There was a 100th appearance for skipper Liam Belcher at hooker, while prop Corey Domachowski and centre Rory Jennings both came off the bench to make their first appearances since October.
Racing, who were looking for their first win in the Challenge Cup this season, made no fewer than 12 changes from last weekend’s heavy Top14 defeat away to Bordeaux-Begles.
When the game got underway in front of a crowd of 8,400, the visitors were immediately reduced to 14 men.
It has to have been one of the quickest yellow cards in rugby history with just some five seconds on the clock when Fijian winger Selesistino Ravutaumada made head on head contact with Alun Lawrence as the Cardiff No 8 attempted to field the kick-off.
Despite being down a man, Racing actually took the lead through a penalty from fly-half Antoine Gibert, but they then conceded a try which, tellingly, was scored down Ravutaumada’s vacant wing.
After in-form centre Ben Thomas made the initial carry up the middle off a lineout, Sheedy put in a cross-field grubber kick and then it was over to the predatory Tom Bowen,
Putting on the afterburners, the teenage winger got to the ball first, took it on the bounce and went outside the cover before diving in acrobatically at the corner.
It was his seventh try in seven outings this season, with Sheedy adding the conversion from the left touchline.
However, the carded Ravutaumada was to make amends on his return to the field.
First he raced over after pulling off a one-two with South African No 8 Hacjivah Dayimani and then he was to be at the centre of Racing’s second try just past the half hour mark.
He was involved in his team being awarded a penalty, through Bowen colliding with him in the air, and, from that, scrum-half Leo Carbonneau took a quick tap with Ravutaumada popping up on his shoulder to slice through.
The Fijian shook off a series of defenders as he burst right up to the line, with Argentine full-back Geronimo Prisciantelli providing the finish.
Cardiff needed to respond with a score before the break and it came in the final play.
An earlier 50-22 from prop Rhys Barratt hadn’t resulted in a score, but when Beetham repeated the trick with a raking touch finder they were not to miss out.
Second row Thornton started and finished the attack, winning the lineout at the tail and then barging his way over after a series of forward carries.
Sheedy added a further conversion from wide out to cut the half-time deficit to 13-12.
When play resumed, it took just five minutes for Cardiff to grab the lead as a succession of pick-and-gos off a Belcher tap penalty culminated in tighthead Assiratti rumbling over the whitewash.
Sheedy again slotted the extras and added a brace of penalties to widen the gap ahead of the impressive Thomas claiming the bonus point try as he looped around co-centre Smit and scythed through to the line, with Beetham converting. It was job done.