Two tries from Rhys Williams saw Cardiff edge out Montferrand 26-20 in a tense match at the Arms Park.
His first try came in the first half, a good chip over the top allowed Williams to demonstrate his lightning pace, outstripping the French defence, tapping the ball on, and triumphantly touching the ball down.
The game ebbed and flowed with no real penetration from either side. Cardiff maintained a seven point cushion after penalties were exchanged.
The real excitement was saved for the final seconds. Cardiff were jubilant as a neat move was started and finished by Williams when he touched down in the corner. Harris dutifully converted and the victory seemed assured.
Immediately from the restart Montferrand poured forward, and intense pressure lead to full back Jimmy Marlu touching down, reducing the lead to just six points.
The ball broke loose in midfield, and was picked up by the now marauding Montferrand pack, were it not for some valiant defending five metres out by Canadian lock John Tait the French side would have snatched victory from the Jaws of defeat.
As it is Cardiff left the Park victorious, with Rhys Williams winning the Man of the Match award, a poignant award, as Williams had recieved heavy criticism after a poor perfomance the last time these sides met,
"I took a lot of stick after that game and I didn't enjoy it at all. I
wanted to put the record straight and show what I could do," said Williams.
"I needed this performance for myself and for the team. I might have
grabbed the tries, but the front five forwards tackled their hearts out
and were magnificent."
Joubert was in a positive mood in post match interviews, "I'm pretty confident we will be there in the last eight. I think we can go
and win at Northampton," said Joubert.
"This game went right to the wire, but it shouldn't have been like that. We
let them back into the game in the last 10 minutes."
If Cardiff can snatch victory at Franklin Gardens next week, they will be favourites to go through to the final eight in the competition.
Cardiff: Tries - R Williams 2; Cons - I Harris 2; Pens - I Harris 4
Yellow cards: J Tait 19, C Quinnell 37
Montferrand: Try - J Marlu; Pens - G Merceron 5
Yellow cards: A Galasso 19, A Audebert 37
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When the Wales squad were asked to nominate individuals who played a big part in their early playing days, Wales and Dragons full back and wing Hallam Amos thought of his former Monmouth School rugby coach John Bevan.
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Bedwas head coach Steve Law and players Nicky Griffiths and Alun Rees extol the virtues of the close knit club as they prepare to host third place RGC 1404 - who are one place head of them on the Principality Premiership points table - on Saturday.
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WRU TV: Hear from inside the Wales camp as Neil Jenkins discusses this weekend's clash with South Africa and how the squad are looking to put in a strong performance to round of the 2016 Under Armour Series