Millions of England supporters, at the game and watching on television around the planet watched on in horror as his fumble allowed the USA to equalise in Saturday's opening World Cup Group C game in Rustenburg.
Speaking to the CT, Marshall said: "I have known Robert since he was 13 and we are very close friends and no-one felt more for him, other than his parents, than me on Saturday night.
Andy Marshall (right)
"I have not spoken to him but I have exchanged text messages with him. He will have felt like he had the weight of the world on his shoulders and he will know when the time is right to talk.
"He has done exceptionally well over the last two years to get where he has today and what we tend to do in this country is build people up to shoot them down. But he will deal with it and I know he has got the character to bounce back.
"I can understand the fans' point of view but from a professional angle I believe it was just a freak thing. If you look at the rest of his game he was solid and bounced back with a top-class save, and I believe he should be judged on the whole game and not just one mistake.
"I also think Fabio Capello will make the right decision and play him again on Friday night when he could do with a solid performance and maybe a world-class save. But I have absolutely no doubt in his ability."
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