WARREN Gatland says his Wales squad's appetite for hard graft will make it even tougher when telling his unlucky 11 that they won't be heading for the World Cup.

In April the head coach named 42 players for the preparations for Japan 2019 and they have been put through their paces in a gruelling camp in Switzerland.

Wales return to play a double-header with England, at Twickenham on Sunday, August 11 and in Cardiff the following Saturday, before another camp in the heat of Turkey.

Gatland's men then take on Ireland at Principality Stadium before the boss whittles his squad down to 31, who will take on the Irish in Dublin before heading for Japan.

The management opted to go with a smaller group that in 2015 but still have a handful of selection headaches – with Dragons lock Cory Hill, hooker Elliot Dee, tighthead Leon Brown and back row forwards Ross Moriarty and Aaron Wainwright, plus their former teammate Hallam Amos, sweating on their places.

Campaign Series:

"When we finally pick the squad and have to deliver the bad news about some of the players missing out, that's going to be really tough," said Gatland.

"It's nice from a selectoral point of view to have so much competition, so much depth within the squad.

"But, seeing how hard this group of players are working at the moment, it's going to be tough. It's going to be quite hard to deliver some of that bad news when it finally comes."

In World Cup year most sides state that they are fitter than ever but Gatland says the conditioning staff have the stats to prove that the players' hard graft is paying off.

"It's been tough on them and the staff because it's been three sessions in the morning and a couple in the afternoon, so long days, but that's what you are here for," said Gatland.

"It's about hard work for everyone and the guys are getting some real benefit out of that. We are really happy with where we are at the moment.

"We have been looking back on some of the figures and numbers from 2015 and we feel we are ahead of where we were then in terms of the training volume, the intensity of training and high-speed metreage.

"So there's a lot of statistical data and we've probably been doing a bit more rugby than we did four years ago.

"Things don't stay the same. They keep moving and getting harder and more competitive and challenging every year.

"We feel we have moved on from the last World Cup and we are really happy where we are."

Grand Slam champions Wales will attempt to extend their 14-Test winning streak when they head to London with Gatland saying his charges need to grasp every chance to impress, be it on the training paddock or in the three games before he makes his final calls.

"We will have a bit of a break when we get home and then start building for those two games against England," said the head coach.

"Then we are off to Turkey for warm weather and that will be in the high 30s. That will be a camp based on heat stress and training about four times a day.

"Then we will come back from there and have that game against Ireland at home.

"That is going to be incredibly important for the players involved because it will be the last opportunity before we name the World Cup squad."