David Warner said that Mahendra Singh Dhoni has been a good helping hand for Virat Kohli. MS Dhoni brought a sense of calmness to his captaincy. He did a great job as captain and he is still doing a great job. However, Warner said Kohli's real challenge would come when he goes through a lean patch as captain. After taking over as full-time captain of the limited-overs teams, Kohli has led India to series wins over England, West Indies and Sri Lanka.