|Pro12: Dragons v Blues|
|Venue: Rodney Parade, Newport Date: Sunday, 27 December Kick-off: 15:05 GMT|
|Coverage: Live on S4C, BBC iPlayer and online; score updates on the BBC Sport website|
Newport Gwent Dragons boss Lyn Jones admits he "hasn't got a clue" why European competition brings the best out of his side.
Dragons have often been the lowest-ranking of Wales' four professional teams.
But they completed a double over French side Pau to finish top of European Challenge Cup Pool Two, having reached last season's semi-finals.
"I haven't got a clue. I just don't know how we do it," said Jones.
However, he suspects facing fresh opponents instead of familiar Pro12 rivals brings a more positive approach from his players.
He says Pau and Dragons players "don't know each other inside out", as can be the case for most of the rest of the season.
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"We play in the Pro12 against each other every year - year in, year out - and we get to know each other and close each other off very quickly," added the former Wales open-side flanker.
"And you come into the European competition, you're up against great players, but we just put our head back and we're a lot more positive on the game.
"And you can be critical and say why can't we be like that in the Pro12, well I don't know, I just don't know."
Dragons did a Challenge Cup double over Stade Francais last season.
French clubs have often fielded weakened teams in Europe's second-tier tournament, but Pau appeared to strengthen their side for Saturday's clash having been beaten 22-0 in Newport the previous weekend.
France star Damien Traille was at full-back, ex-New Zealand fly-half Colin Slade at 10 and 6ft 3in veteran Fiji powerhouse Sereli Bobo, 39, started on the wing.
Pau also brought on All Blacks legend Conrad Smith at centre for his debut.
But the hosts could not match Jones' Dragons, who host Castres in January before travelling to Sale hoping to ensure a place in the quarter-finals.
Jones praised the efforts of former Wales Under-20 wing Ashton Hewitt and the more experienced fly-half Jason Tovey.
"We had Ashton Hewitt playing against Sereli Bobo from Fiji on the other wing and that was a great contest," he said.
"And fair play to Ashton, he hung on to his shoelaces all night long and made sure he couldn't run anywhere.
"Tovey took his opportunities well and he scored a good 40m try, turning on the burners as Jason can, but he kicked well out of hand.
"And last week we had a predominantly right-footed game and this time we had a predominantly left-footed game and I think it caught them by surprise."