Coach Eddie Jones said England face a mental block when closing out matches after his side blew a 31-0 lead in extraordinary fashion to draw 38-38 with Scotland in their final Six Nations game on Saturday.
Jones's team needed an 83rd-minute try by George Ford to salvage a draw that left Twickenham in a state of disbelief as the Scots, who had not won there for 36 years and looked set for another hiding, somehow scored 38 unanswered points.
"It's a bit of a recurring theme for us, we've experienced this at least three times in last 12 months where we've taken control, let our foot off the gas and been unable to get it back," Jones told reporters.
"It's 100 percent mental - there was no physical difference. It's not something you can fix easily but we know what the problem is. It's going to take some digging deep into the team psyche but I think it's a good lesson for us before the World Cup.
"The first half was exceptional and we should have been ahead by more but the finishers did exceptionally well to get us out of jail."
England were cruising after half an hour through tries for Jack Nowell, Tom Curry, Joe Launchbury and Jonny May, and a repeat of the record 61-21 Calcutta Cup thrashing of two years ago looked on the cards.
Scotland, however, got a toehold before half-time with a try by Stuart McInally then added five more tries after the break as England's defence and organisation fell apart.
Jones blamed the collapse on a combination of factors. "We didn't have the discipline to just keep doing the simple things over and over again," he said. "Maybe we got a bit seduced by the scoreboard.
"Scotland came back really well -- plenty of heart, pace and endeavour. Guys who were playing poorly turned their game around."
Scotland coach Gregor Townsend described it as the most unusual game he had been involved in as coach or player. "When you think of the team we are up against and the defence they've got, it was a unique performance," he said.
"I feel a lot of pride that the players have not only taken the game to the opposition but scored some great tries. Sam Johnson's was one of the greatest tries in Scottish rugby history."
Like most of the shell-shocked fans leaving Twickenham at the end of another Six Nations "Super Saturday" that more than lived up to its billing, Townsend said it was difficult to know how to feel.
"I'm really happy with the draw but the players are absolutely gutted - which is incredible from where they were in the game," he said.
"We showed a lot more intensity and cohesion in our defence in the last 10 minutes of the first half but to score another five tries in the second half is still hard to believe.
"We got some momentum and they had to change the way they played, and we were getting confidence from that."
Captain McInally, who sparked the turnaround with Scotland's first try when the hooker somehow held off high-speed winger May in a charge for the line, was just as confused about his feelings.
"With a minute to go you dare to dream we might have done it," he said. "At half-time we spoke about winning the second half. Did we think we would score 38 unanswered points? Probably not, but we scored some great tries.
"It was disappointing to concede right under the sticks at the end but I'm really pleased that we've retained the Calcutta Cup."