Gambhir was speaking on ESPNcricinfo's T20 Time Out soon after Sharma led Mumbai Indians to their fifth IPL crown, by beating the Delhi Capitals by five wickets in Dubai. Apart from leaving his mark as a captain on the field, Sharma killed off the chase by scoring a quickfire 68 to set up an easy win.
"If Rohit Sharma doesn't become India's captain, it's their loss, not Rohit's," Gambhir said. "Yes, a captain is only as good as his team and I completely agree with that, but what are the parameters to judge a captain on who is good and who isn't? The parameters and benchmark should be the same. Rohit has led his team to five IPL titles."
Gambhir had earlier in the tournament spoken of the need for Virat Kohli, India's current captain across formats, to be accountable for the Royal Challengers Bangalore, who are yet to win an IPL title in 13 seasons - Kohli has been captain for eight of those. The franchise have made the playoffs only three times under Kohli's captaincy - this year, they crashed out in the Eliminator to finish the tournament with five consecutive losses.
"We keep saying MS Dhoni is India's most successful captain. Why? Because he has won two World Cups and three IPLs," Gambhir said. "Rohit has won five IPL titles, he is the most successful captain in the history of the tournament. Going forward, it'll be a shame if he doesn't get India's white-ball or just T20 captaincy. Because he can't do much more than this. He can only help the team he captains to victories. So if he doesn't become India's regular white-ball captain, it will be their loss."
Gambhir also clarified this was by no means a suggestion that Kohli's captaincy was "poor", but merely an observation of who is more suited to the job, given they both started captaining their IPL franchise around the same time, in 2013. Kohli took over the captaincy mid-season that year from Daniel Vettori, while Ricky Ponting stepped down to hand over the reins to Sharma after a poor start.
Gambhir, who led Kolkata Knight Riders to two IPL titles - in 2012 and 2014 - even suggested India could consider a split-captaincy model going forward, with Kohli continuing to lead in Test cricket and Sharma taking over the white-ball captaincy.
"They can also consider split-captaincy," he said. "No one is poor. Rohit has shown in white-ball cricket how big the difference is between his and Virat's captaincy. One player had led his team to five titles, the other hasn't won yet. I'm not saying this because Kohli is a poor captain. But he has received the same platform that Rohit has, so you have to judge both of them on the same parameters. Both have been captains in the IPL for the same length of time. I feel Rohit stands out as a leader."