Kolkata: Taking an apparent dig at England stand-in twenty20 skipper Graeme Swann, batsman Kevin Pietersen on Saturday said it was improper for a professional to write a book in the middle of his career.

"I still do not agree to anyone writing a book in the middle of his career," Pietersen said after piloting England to victory in the one-off twenty20 game at the Eden Gardens here.

Pietersen scored a 39-ball 53 as England defeated India by six wickets to win their first match during an otherwise disastrous tour.

Pietersen said the controversy over Swann's book has not affected relations between the two.

"That (controversy) was something around for a day or two. But that had nothing to do with our relationship," he said while holding a joint media meet with Swann.

Swann in his autobiography, "The Breaks Are Off", had written that Pietersen was not a natural leader and should not have captained England.

Swann also concurred with Pietersen that the controversy did not affect the dressing room atmosphere. "Whatever had happened did not affect the dressing room atmosphere," he said.

Pietersen said he played the match with a broken thumb to fulfil his desire to play at Eden Gardens.

"I tried some medication and took a risk, thank God it worked. It was one opportunity to play in a great stadium," he said.