He does not quite know which way the series will go but former England skipper Michael Vaughan is quite sure that Indian captain Mahendra Singh Dhoni would be pushing more aggressively for a win than his "defensive" rival Andrew Strauss in the Tests starting July 21.

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"Dhoni has been exceptional. He is a positive cricketer and he thrives on the leadership qualities he has as a captain. He seems to get the best out of all his players. He is quite an aggressive captain," Vaughan was quoted as saying by the Daily Telegraph.

"He is not scared to make moves and maneuvers his field to give the opposition a chance to play aggressive cricket as well. That will be the challenge in this series," he added.

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In comparison, Vaughan said Strauss is the one who would first like to make sure that the game is safe before trying to attack.

"He (Strauss) is quite a defensive captain. He likes to make the game safe before he attacks, but he has created a unit that plays for each other, and that is why you feel they can go on and be the No.1 team in the world," he said.

The 36-year-old Vaughan said the outcome of the India-England series would depend a lot on how the two captains respond in different situations.

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"It may come down to which captain is the more adventurous because I see a lot of runs being scored. The pitches will be good and it may come down to which captain gambles in those key periods," said Vaughan.

England are set to host India for four Tests, five ODIs and one Twenty20 International, starting from July 21.