Former World Cup-winning coach Clive Woodward believes inadequate planning led to England’s downfall against Australia at the weekend.
Woodward lamented the decision to turn down three kickable penalties at 20-14 down as the hosts pursued a seven-pointer.
Woodward laid the blame at Lancaster’s door, saying he should have discussed all possible match scenarios and decisions prior to the Twickenham Test.
"If you are coaching any team, the biggest thing is trying to be smart ahead of the game," Woodward told Sportsweek.
"You have to be smart and a lot of that smartness comes from the way you train, the way you think and the players you pick," he said on the BBC Radio 5 live programme.
"The key thing is getting these things in players' heads before they head out onto the pitch so you will know what will happen in every single situation.
“There is no point reviewing the video after you have lost, you have to review things before you go in and that is the secret to coaching.
"You must not make decisions in the heat of battle. It is a brutal business international rugby and these decisions are absolutely crucial.”
Woodward did, however, say Lancaster had an opportunity to rectify matters by guiding England to victory over the Springboks on Saturday.
"England have a week to put this right, and I think they will have a great week and it is a big opportunity for Stuart Lancaster to make his mark and turn this around."
Captain Chris Robshaw said the Cook Cup defeat was an educational experience but defended his choices, saying "hindsight is a wonderful thing.”
England had come close to scoring when No.8 Thomas Waldrom had an effort ruled out, which Robshaw felt would have been a turning point in the match.
"If Tom Waldrom gets that ball down it is a huge momentum shift. It is easy to have ifs and buts after the game.
"We will have a sulk after this game but you have to learn quickly. If we had taken those points it could have been a different result," he said.
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