Andrew Strauss has revealed that the main reason behind his shock retirement today was his form with the bat.

Strauss, who will be replaced as England Test captain by Alastair Cook, called time on his professional cricket career having been replaced at the top of the rankings in all forms of the game by South Africa.

The 35-year-old claims that he had been considering retirement for a while, and that his lack of runs was a key factor behind his decision.

"It's a very tough decision to make but for me the driver to it all was, quite frankly, my form with the bat," said Strauss.

"In truth I haven't batted well enough for a long period of time now and I think for a captain to perform his role properly it's important that firstly you're not a passenger in the side but also that people aren't speculating as to whether you should be in the side.

"I think that would have been a big distraction to the side going forward. I know with my motivation and energy levels that I wasn't going to improve batting wise, I'd run my race. It hasn't been something that's happened overnight, it's been a gradual feeling that has grown over the last six or 12 months."

Strauss is one of only five players to have played 100 or more Tests for England, and is their second most successful captain of all time.