Sri Lanka had lost 9-0 to India across all formats a few months back and were therefore never expected to provide the ideal preparation for what will be a challenging trip to South Africa for the world's top-ranked test team.
After the rain-curtailed opening match at Kolkata's Eden Gardens ended in a draw, Kohli's men crushed the visitors by an innings and 239 runs in the second test, matching their biggest winning margin in the longest format.
India's batsmen compiled up a mammoth first-innings total against Sri Lanka's toothless attack, while the spin duo of Ravichandran Ashwin and Ravindra Jadeja combined to pick up 13 of the touring side's 20 wickets in Nagpur.
But it was Ishant's match haul of 5-80 that the skipper described as the standout bowling performance of the match.
"Even on this wicket, to have that kind of bounce and trouble the batsmen regularly, I think Ishant was outstanding," Kohli said at the post-match presentation on Monday.
"Although the spinners obviously did a good job for us, I think Ishant was the standout bowler in this game."
India's biggest victory margin until Monday's win was against Bangladesh in Dhaka in 2007, a test in which Ishant made his debut as a 18-year-old.
The lanky right-arm paceman was marked as the future leader of India's fast bowling attack and while he has gone on to play 78 tests he has failed to live up to those lofty expectations.
After falling behind Mohammed Shami and Umesh Yadav in the pecking order, the emergence of Bhuvneshwar Kumar as a swing bowler has only made it tougher for Ishant and his chances have largely come due to the unavailability of other fast bowlers.
He played three out of four tests against Australia earlier this year after Shami was ruled out with a knee injury but played no part in three tests in Sri Lanka in July-August, though he kept himself fit and in form by picking up 20 wickets in four matches for Delhi in the Ranji Trophy.
Ishant would probably not have played in Nagpur had Kumar not withdrawn from the final two tests to get married and Shami was not ruled out due to a slight injury concern.
In Nagpur, he extracted good bounce and movement from a batting-friendly track, which could prove crucial in South Africa with India set to face wickets that are expected to aid the faster bowlers.
"The way Umesh and Shami and even Bhuvi were bowling was tremendous. I didn't take much wickets in the last 12 tests I played, specially in India. They deserved to get a chance before me," Ishant said after Monday's win.
"The problem for me was the wicket column was always empty. But now I am getting wickets, I am felling pretty good about myself.
"It's a healthy competition the way everyone is performing. When you get an opportunity you have to take wickets."
First Published: November 28, 2017, 2:17 PM IST