England defence coach Mike Ford has launched a damage limitation campaign over his comments about Andy Farrell.
Ford says Farrell can still have an impact on international rugby union
Earlier this week, Ford suggested the 32-year-old ex-rugby league star might never succeed in the 15-man code.
"He is getting to grips with it but it is probably a bit too late, with his age, to be where he wants to be," Ford said on Sunday.
But on Wednesday he stated: "I think he will have an impact on this tournament and even after the World Cup."
When he made his initial comments Ford suggested that the year Farrell missed because of injury when he first crossed codes would prevent him from hitting the heights he achieved in rugby league.
However, he has now said that Farrell could play for "at least another two years" at the top level in union.
I'm one of his biggest supporters in terms of him changing codes
Farrell, who is set to be on the bench for England's vital Pool A game against Samoa on Saturday, has struggled to establish himself in his national team since the high-profile switch of codes.
In 2005, Ford played a major role in persuading the former Great Britain rugby league captain to move to rugby union.
Former rugby league scrum-half Ford was then the head coach at Saracens, who Farrell joined in a deal that was partly funded by the Rugby Football Union.
"I signed him because I knew that he was a very special player and the attributes that he had in rugby league he could translate to rugby union, at number 10 or 12," insisted Ford.
"The fact that he was a goal-kicker and a leader was a double bonus.
"He is a very good technical player, in terms of passing, kicking, tackling and decision-making, and he has a real 'follow-me' attitude.
"Those players don't come along very often and when Andy decided to think about changing to rugby union it was a no-brainer for someone like myself, who knows him so well, to try to get his services.
"I'm one of his biggest supporters, in terms of him changing codes. I did that from day one, during his 12 months out with injury.
"And when he got back - in the debate about where he should play, at number six or 12 - I always said it should be in the centre."