Paris - France's South Africa-born lock Paul Willemse said on Sunday he was "scared" by the potential in the squad after opening their Six Nations campaign with a 24-17 victory over England in Paris.
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Willemse, who played for his hometown side of the Blue Bulls in Pretoria before qualifying for Les Bleus on residency grounds last year, was one of 11 players in the starting line-up with less than 20 Test caps.
"The scary thing is that I believe there's lots of room for improvement in our team still so it gives me confidence in the future," Willemse told AFP.
"It's a fresh group. All of us have this one mentality to go forward for the next World Cup and it helps a lot. Most of the team is starting our history now, it's like a clean slate," the 27-year-old added.
Willemse lined up alongside a fellow South Africa-born player in Bernard Le Roux, who hails from the Western Cape, in their first appearance combining as second-row partners.
"We haven't spent too much time playing together. We did our World Cup preparation for one week before I got injured so we spent a bit of time together there but the last two weeks went really well," Willemse said.
"We sometimes speak Afrikaans together on the pitch but we kind of have a rugby language on the field.
"So you don't speak any language, you speak the rugby language. We have our jargon, talking with certain words. It helps."
Willemse and Le Roux made 34 tackles between them as new defence coach Shaun Edwards' impact was seen immediately.
The hosts held out England for almost an hour after spending large parts of the game without the ball in their own 22-metre area.
"What we've been working on for the last few weeks is really using our defence as an attack. Using our defence as a weapon and that's our plan," Willemse said.
"The key for that is to do it for 80 minutes. It's really draining but if we're capable of doing that for 80 minutes it's awesome."
France host Italy at the Stade de France next Sunday and Willemse said his side must learn from the victory over Eddie Jones' World Cup runners-up.
"Our focus again will be to put the pressure on and do it for 80 minutes and not to release. We have to make sure they're under pressure the whole time because if you leave it they can come back into the game," he said.