Wales coach Warren Gatland has claimed that Ross Moriarty brings something different to the country's Rugby World Cup squad.

The 21-year-old Gloucester flanker, who made Wales's 47-man World Cup training squad, was called up to the tournament squad following an injury to Eli Walker, who was himself a late call-up in place of Leigh Halfpenny.

"For Ross, he was unlucky in the first place to miss out on the squad. He made a huge amount of progress during his time with us in terms of where he started from in terms of fitness and a conditioning point of view," Gatland told reporters.

"He hadn't had a pre-season for the last two years and he gives us a bit of X factor, and it is a great opportunity for him to get into the squad."

On Walker's injury, Gatland added: "Eli has been very unfortunate in the last couple of years with the injuries he has picked up. He is very disappointed but obviously he understands it is about putting the team first, and he understands the process we have to go through. But the door is not fully closed for him and there might be an opportunity for him later in the tournament."

Wales play Uruguay in their opening World Cup fixture at the Millennium Stadium on September 20.