SAMSON Lee's World Cup dream is in the balance but Wales boss Warren Gatland says he "won't be going down on bended knee" asking legendary prop Adam Jones to return.

Gatland says that the Scarlets tighthead is "50/50" for England 2015 after rupturing his left Achilles in the opening exchanges of last weekend's Six Nations win against Ireland.

Lee, 22, has been an influential figure since usurping Jones on last summer's tour to South Africa and started seven of the eight Tests this season, only missing out against Scotland because of concussion.

His rise prompted Cardiff Blues tighthead Jones, who won 95 Wales caps, to retire from Test rugby when left out of the squad for the Six Nations.

Gatland has plumped for Aaron Jarvis and Scott Andrews for this weekend's Six Nations finale in Italy while other World Cup options will be Rhodri Jones, who is currently out with a shoulder injury, and Tomas Francis, the Exeter prospect who has been training with the squad.

None have the scrummaging experience of Adam Jones but the head coach says he won't implore the man who was the cornerstone of his 2013 Lions side to reconsider his retirement.

"I was surprised at the timing of his announcement," said Gatland. "He was not out of our thoughts and we had played a little bit of phone tag, leaving messages and going backwards and forwards.

"If he has changed his mind and wants to get on the phone and say I made a rash decision, retired too early and want to be part of the World Cup squad, that is a different conversation.

"At the moment I will not be going on bended knee ringing him saying 'please come back we really desperately need you'. For us it is about dealing with the other players."

Lee will go under the knife next week and the expected layoff is six months with Wales' World Cup squad named after their second warm-up game against Ireland at the end of August.

The first game of the tournament is against Uruguay on September 20 and Lee would need to be back to full fitness by the encounter against England at Twickenham on September 26.

"For everyone with that sort of injury, it can be two or three weeks either side. He might be lucky and rehab and recover well or he might be slow and miss out. I think he is a 50-50 chance at this stage," said Gatland.