England coach Eddie Jones believes he has 80 per cent of his World Cup squad locked down but remains hopeful of unearthing a hidden gem before the 2019 tournament in Japan.
The Australian has been in charge of England since their miserable showing as World Cup hosts in 2015, and has won 20 of his 21 matches at the helm - his only loss coming against Ireland in the Six Nations.
Jones has consistently looked for different options to give him the best possible chance of leading England to glory in Asia.
His latest training squad ahead of the November internationals with Argentina, Australia and Samoa included the uncapped duo Marcus Smith and Tom Dunn - while Jack Clifford has replaced the injured Billy Vunipola.
Smith and Dunn have caught the eye in the Premiership this season and Jones intends to keep giving untested players a chance to shine.
"What I'd like to find is like a Nehe Milner-Skudder someone like that, [who] just comes out of the blue and gives you something different in a World Cup year," the coach told the England Rugby website.
"I reckon now we've probably got about 80 per cent of the squad about right but we're looking for that X-factor rookie to come out and there is a place for that sort of player.
"It might be someone like Marcus Smith, who knows?"
One thing Jones has no intention of changing is England's style of play, which may not be as flamboyant as the All Blacks but can still be effective.
"Just because it's popular, it doesn't mean it is right," he added.
"Spending your whole life on your phone is popular but that doesn't mean it is right.
"There is a certain sort of rugby we need to play to win the World Cup and it is not going to be popular rugby - we'll play the rugby that suits us.
"We're going to play our own rugby, we don't need to copy New Zealand."