'We haven't reached our peak,' insists Manu Tuilagi
Ahead of the quarter-final encounter against France, England centre Manu Tuilagi insists there is plenty more to come from Martin Johnson's side - and vows to wear the right gumshield next time.
The Leicester Tigers centre was fined £4,800 for wearing a sponsored mouthguard in the 41-10 win over Georgia.
Tuilagi, whose brother Alesana was fined last week for the same offence, also wore the mouthguard against Argentina.
The Rugby Football Union (RFU) said Tuilagi's breach was a "genuine error".
Tuilagi, who is expected to feature in England's quarter-final against France on Saturday, said of his fine: "I didn't know I had worn the wrong gumshield and I got fined for it."
The 20-year-old insisted both he and his brother, who plays for Samoa, did not deliberately flout the International Rugby Board's strict advertising and sponsorship rules.
"We always wore the same mouthguard, mine is the England one from the under-18s, but it's not allowed in the World Cup," added Tuilagi, who has impressed in New Zealand.
"I coloured it in with marker pen for the Romania game. I wore it against Argentina but they didn't know."
An RFU spokesman said England had not been fined for any other breaches.
"Manu wore a mouthguard where the branding was visible in the Georgia match when it shouldn't have been so therefore he's been fined 10,000 New Zealand dollars," said the spokesman.
"It was a genuine error and he's trying now to focus on Saturday's game."
Meanwhile, Jonny Wilkinson, who has a niggling shoulder injury, took part in a light training session on Tuesday.
But concerns persist over centre Mike Tindall, who suffered a leg injury in Saturday's victory over Scotland and sat out training.
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