Guilty conscience: Emile Heskey admits his part in Rio Ferdinand's knee injury made him feel awkward

"What happened was that I tried to turn the ball round the corner and fell backwards onto him but his leg was in a position where he couldn't actually move it,’’ said Heskey.

"There was nothing he could actually do but knowing he was out of the World Cup, when he was our captain and has been a great player through the years for England and for his club, and knowing that because of an incident between me and him he was out of the World Cup was disappointing.

"I spoke to him afterwards and he told me there was nothing I could do but it was still difficult for me."

Heskey has also defended Wayne Rooney over his conduct in Monday's practice match against the Platinum Stars.

Rooney was booked shortly after his introduction at half-time and referee Jeff Selogilwe has warned the England striker he risks getting sent off during the World Cup unless he curbs his behaviour.

But Heskey does not see a problem. Tipped to partner Rooney in Rustenburg this weekend for the Group C opener against the United States, the 32 year-old felt his strike partner gave England a much-needed lift.

"A lot was made of it but at times his passion has been misread for anger," Heskey said. "When he came on the pitch he got the lads going. We probably needed that because we were a little bit flat.

"He picked us up and gave us the boost we needed. It is not anger. He just wants to win. He is so passionate, he wears everything on his sleeve."