In the 21st over of England's second innings at Lord's, MS Dhoni did something many commentators - former cricketers all - claimed they had never seen before. Two balls into Ravindra Jadeja's seventh over, Dhoni got rid of his helmet and stood further behind the stumps than usual. He kept doing so whenever Jadeja bowled to left-hand batsmen. For right-hand batsmen, he would return to the normal position of standing up to the stumps.

As the unusual scene of Dhoni standing close for the medium-pacer Bhuvneshwar Kumar and back for the spinner Jadeja played out, the experts began to guess what exactly he was trying to do.

Some thought Dhoni was being funky for the sake of it. A little too funky. Others said they had last seen this in an Under-11 match. Some felt an edge off Jadeja's pace and extra bounce would be easier to take if the keeper was standing back. The majority agreement, though, was that on an uneven pitch in a tense Test, Dhoni was a little too worried about conceding byes off Jadeja, who was firing the ball into the rough - an extremely cynical view to take, even for the sternest critics of Dhoni's captaincy.

After India's 95-run win, Dhoni revealed why he had stood back. It did have a lot to do with the rough, the uneven bounce and Jadeja's pace, but the move was necessitated because of the laws of cricket.

A catch had just lobbed wide of Virat Kohli at leg gully. Dhoni needed two leg gullies - or a leg slip and a leg gully - but that would mean sacrificing short fine leg to meet the rule of not having more than two fielders behind square on the leg side. No fine leg meant an easy getaway sweep shot.

So Dhoni went for a home remedy. He asked Kohli to move squarer for the meatier edge, and he took a couple of steps back so he had the time to go for the fine edge down the leg side.

"I wanted to have a fielder there," Dhoni said of his new position. "But according to the rules of the game you can't have three fielders there. I wanted Virat to stand slightly wide of where he was standing because anything like a snick or a faint edge on the leg side would go between him and me. So the plan was to stand behind and cover that."

Dhoni did not get to show off his genius because no edge went that fine. In Jadeja's next over, though, one flew off Alastair Cook's glove but fell short of Kohli. The bigger danger of this plan, however, was of Dhoni missing a stumping or watching the batsmen use their feet comfortably. England's batsmen, though, did not do that.

"If the batsmen kept stepping out and playing, I would have had to go in," Dhoni said. "They didn't really step out so I had the liberty of standing back and trying to catch the ball at both ends, but nothing really came to us.

"The good thing was, they didn't really step out and miss one because that would have been a perfect thing for the commentators to talk about."