Damian Penaud scored a hat-trick of tries as France thrashed Namibia 96-0 in a World Cup Pool A match in Marseille on Thursday, but star scrum-half Antoine Dupont went off injured after a high tackle.

Dupont, who had scored a try and produced two decisive cross-kicks, left the pitch in the 46th minute nursing his right cheekbone after Johan Deysel got his contact completely off-kilter in a nasty head-on-head clash and was sent off.

Coach Fabien Galthie left no room for doubt for their third pool match in selecting a full-strength team that outclassed the Namibians in every facet of the game which produced a French record 14-try mauling.

But the overwhelming victory might have come at a high price, as Galthie faces an anxious wait after his talismanic skipper was whisked off to hospital.

Dupont, yet to lose a match on home soil when captaining France in 14 matches, showed his awareness with a cross-kick that Penaud gathered for France's opening try in the sixth minute.

Jonathan Danty marked his return from injury with the second try after Louis Bielle-Biarrey produced a fine inside pass, rapidly followed by Charles Ollivon finishing off a flowing counter-attack.

Penaud grabbed his second to guarantee France the desired attacking bonus point, quickly followed by Danty, who barrelled over from short range.

Thibaud Flament crossed for the home side's sixth try after an Anthony Jelonch break from a ruck and Dupont was next over the line with Namibia left answerless to the speed and efficiency of the French.

Dupont produced his second decisive cross-kick of the match for Bielle-Biarrey, Ramos' seventh conversion leaving it 54-0 at half-time.

But the Toulouse scrum-half's second period was short lived as Deysel made head-on-head contact with him in a tackle and Dupont was forced off for a head injury assessment and the Namibia captain red-carded.

It also saw Divan Rossouw's intercept try scrubbed from the books to rub salt into Namibia's wounds.

Dupont's replacement Baptiste Couilloud didn't linger once he got on, played in for a try by Peato Mauvaka as Namibia were left with the stark realisation that they were a man down for the final 35 minutes.

Penaud grabbed his third try to match Vincent Clerc (in 2007) and Ugo Mola (1999) in scoring a hat-trick in France's two other matches against Namibia, also at World Cups, and fellow wing Bielle-Biarrey went long-range for his second.

Melvyn Jaminet, and a late penalty try, accompanied by 12 Ramos conversions helped wrap up proceedings as the hosts extended Namibia's World Cup losing streak to 25 games. (AFP)