Eddie Jones looks to blame 2015 World Cup exit under Lancaster for England's mental fragility

Eddie Jones believes England are suffering from a fault line exposed during the 2015 World Cup as he plans to recruit outside help to work on reshaping his players' minds.

Mirroring the collapse in Cardiff earlier in the Guinness Six Nations, England fell apart in the second half against Scotland as a 31-0 lead was squandered with only a converted injury-time try by George Ford salvaging a 38-38 draw.

It continues a theme that initially developed on last summer's tour to South Africa when strong positions were surrendered in the first two Tests.

Jones insists the flaw evident on Saturday was a result of England's traumatic group from their own World Cup four years ago, but is adamant it will be rectified in time for Japan 2019.

"It's about how the team thinks under pressure. It's like we have some hand grenades in the back of a jeep and sometimes they go off when there's a lot of pressure. We have a few of them and we've got to get rid of them," Jones said.

"The team has probably had it since the 2015 World Cup and we've been working on a process to fix it. We will get it right, but it takes time.

"Whenever you have a difficult tournament or difficult games, there's always a lingering thought process there. Sometimes it takes longer than you'd like to fix it, but it is fixable.

"It comes in when you get under pressure, a lot of pressure, and you can't work out a way to get back to what you want to do.

"I've got one person that's going to help us that's a bit of an expert. I'm not sharing that name with you now. I haven't used her before."

Sam Burgess at RWC2015

Jones is confident the summer-long pre-World Cup training squad offers enough time to work on the fragility seized upon by Wales and Scotland.

"When we won 18 games in a row, we still had those problems. And they have come to the fore in a couple of games recently which is beneficial for us because it's made it quite clear what we have to fix to be the best team in the world," he said.

England's most capped scrum-half Ben Youngs disputes Jones' explanation for why the team is vulnerable to self-inflicted wounds, although there was no hiding his frustration at a bewildering disintegration against the Scots.

"I wouldn't agree with that at all. I don't think it's pressure, we just need a better understanding of where the momentum of the game is and what we want at that current moment," Youngs said.

"We are looking at ourselves in the mirror going: 'What have we done'? You can't be that ruthless in the first half and then be so toothless in the second.

"We thought the job was done and it was far from done. We were too loose, too flippant with the ball. Disappointing. There's going to be a lot of reflection on this one."

Jones brought off Owen Farrell in the 71st minute with the match entering a critical phase and the captain later admitted "we probably gifted them the momentum swing, me more than anyone".

Mike Brown and England leave the field dejected in 2015

Farrell had gifted tries to Stuart McInally and Finn Russell and was also lucky to escape a card for a late shoulder-led tackle on Darcy Graham.

"We just needed a change and we needed someone to change the momentum of the game," Jones said.

"Henry Slade and Manu Tuilagi both still had enough in them to stay on, so it then became a decision on whether to replace Owen and we thought it was the best decision for the team at that stage.

"Owen lost a bit of his edge. We know George is an excellent player who can bring something different to the table. We ended up getting a draw due to George's brilliant play.

"It's always a team loss. You never lose because of one player. Owen's the hardest taskmaster in the world and he'll be disappointed with his game."