Kevin Pietersen says the frustration he has exhibited during England's tour of West Indies has been building up since the humiliating Test and ODI defeats against India and was compounded by the team's continuing poor show in the Caribbean.

"The first half of the winter was a shambles under my leadership. We didn't come close to winning a game in India and we didn't come close to winning a game here before we won on Sunday - except for the mathematical error on the West Indies' part in Guyana," Pietersen told BBC.