The Hampshire batsman made his comeback appearance on Monday in the emphatic warm-up win over Bermuda after breaking a rib in the opening match of the Commonwealth Bank series in Melbourne in early January.

He scored 43, and eased fears about his fitness by running around unhindered in the field for the entire Bermuda innings to confirm his availability for England's World Cup campaign.

"I batted for about 45 minutes to an hour against Bermuda and I felt fine - there were no restrictions at all," said Pietersen.

"I was diving around in the field, I've been bowling in the nets and I've been batting without any discomfort at all so I'm raring to go."

But as he enters his first World Cup since qualifying as an England player nearly three years ago, Pietersen concedes he may have to adapt his hard-hitting style to the conditions.

Pietersen has emerged as one of the world's most exciting players with an attacking brand of strokeplay.

Yet he is prepared to play in a far more conservative manner if the pitches continue to be as slow as the practice pitch at Arnos Vale, where England face Australia in their final warm-up match on Friday.

"From what I've seen of the first practice wicket, the conditions are going to be similar to the series we played in India last year when the wickets were pretty low and slow," he explained.

"All the matches played so far have only been played on the practice wickets and not on the big grounds and they could be different again.

"We will have to go out there and adapt to the situation and the teams that adapt the best are going to be best suited for this competition."

But he stressed: "I've had to adapt before and I can do it again. I had to adapt to the sub-continent and I've had to do it on occasions in Australia and I've had to nudge and nurdle for hours at a time on occasion.

"It's one of those things that has to be done and it's one of those things that will be done because you have to play the situation."

He also returns to a side boosted by their surprise success in the Commonwealth Bank series in his absence, a triumph which has transformed the atmosphere in the dressing room.

"I was out in Australia for nine weeks and we didn't come close to winning a game," conceded Pietersen.

"The morale wasn't fantastic and there wasn't much banter around the dressing room when we were getting hammered like we were.

"To watch the boys out in Australia come back from where they were to win the competition was fantastic and when I met up with them at the airport last week the camaraderie was back and everyone was positive - it was a 180-degree spin around compared to what it was like when I was out in Australia."