England's players have been told to ditch their mobile phones if they want to win the World Cup.
The advice comes from England's visual awareness coach Sherylle Calder, who has an extraordinary record of success. She helped the England squad which won the World Cup in 2003, and then did the same with her native South Africa four years later.
She has worked with golfers such as Ernie Els, and she has also advised at Bournemouth football club.
Sky Sports rugby expert Will Greenwood sang her praises in the studio on Monday, but when she addresses the players at a training camp in Portugal on Tuesday she will tell them to restrict the amount of time they spend looking at their mobiles.
"In the modern world, the ability of players to have good awareness is deteriorating because of mobile phones. We will be working hard on awareness, which helps you make effective decisions under pressure," she said.
"If you don't see something, you can't make a decision. We're going to work on skill levels and making good decisions under pressure.
"We have seen in the last five or six years, when we assess elite players in different sports, that there is a decline in skill levels."
"When you look at your phone, you're losing awareness. There are no eye movements; everything is static. We are losing the ability to communicate. All those skills are declining."
Calder says the amount of time young children spend looking at their phones could affect their development.
"We do a lot of work with young kids as well and we've found that reading skills are deteriorating," she said. "But we don't only train the eye movements, the ability to judge and the ability to recognise early - we also train the brain.
"I use the analogy that we develop skills by climbing trees, walking on walls, falling off and learning all those visual motor skills which people aren't doing any more. Young kids spend time on phones so those instinctive, natural skills are disappearing."
England's players won't be under orders to ditch the phones - Calder's advice is just that.
"There won't be rules - we are going to advise," she said. "We can't stop them but we will teach good behaviours. We've got time until 2019. That is our aim."