Zaheer conceded runs in the two matches -- against Sri Lanka and Bangladesh -- India has played so far in the tournament without taking any wicket but Kohli said the team is not worried about his form.
"Zaheer bhai has not done that badly. He is such an experienced bowler that he can his rectify mistakes and come out with a strong performance. There is nothing to be worried," Kohli said after the team's practice session at the Sher-e-Bangla National Stadium ahead of Sunday's match against Sri Lanka.
Kohli said the Mahendra Singh Dhoni-led Indian side will have to play their best to beat Sri Lanka.
"Sri Lanka and India have played a lot between themselves in the last few months and we know the strength and drawbacks of each other very well. It will be a tough match tomorrow and we want to it," said the young right-handed batsman.
Asked about his personal form in the tournament so far, Kohli said he is looking to play a longer innings against Sri Lanka. The Indian team had their optional practice session on Saturday without vice-captain Sehwag, who decided to stay put at the team hotel, but Kohli said there was nothing to worry about as the dashing opener was fit and fine.
The players first played football for around half an hour and then got down to fielding drills with coach Gary Kirsten in thick of the action.
Later, the Indians shifted the action to the nets just outside the stadium where they had batting and bowling sessions.
Kohli, who was the skipper of the Indian colts that won the Under-19 World Cup two years back in Malaysia, wished good luck to the current members of the junior team who will be defending the title in New Zealand this month.
"Under 19 World Cup is a big platform to graduate to the higher level. I wish them good luck," he said.
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