Having claimed just four wickets in nine matches at a poor average of 71.50, Kuldeep was eventually dropped from KKR's playing XI.
Speaking exclusively to Hindustan Times, Kapil said that after he was dropped, he had a session with him.
Kapil revealed that there were some minor errors that had crept into his bowling action.
Further, regular international tours had deprived him of the basic drills and training to keep going.
As a result, he took the charge of getting the basics right.
"He was mentally down. I asked him to bowl round the wicket. I knew, with his action he will naturally turn the ball more from the other side. As soon as he got his confidence back, I told him to switch to over," said Kapil.
Kapil admitted that Kuldeep underwent rigorous training at Rovers club in Kanpur from 7 AM each day bowling for several hours.
After he started to get his rhythm back, he was asked to do the same from over the wicket.
While the process was tiring, both were adamant, and the outcome was sensational, resulting in a beautiful performance against Pakistan.
Kapil also said that the other problem with Kuldeep's bowling was that he had started bowling fast, but flat.
The pressure of playing in IPL made him experiment with his natural bowling style.
"I want to bowl fast, he told me before IPL. But, what he did during the tournament was bowl flat. If you don't flight the ball, it won't turn," Kapil added.
To script success in England, Kapil urged Kuldeep to follow a small trick.
He asked him to get his left arm high and use his shoulder more than his wrists.
"He did not have a firm grip on the ball. He needed to lock his wrists and use more shoulder. That way, he could generate pace, even while flighting the ball," suggested Kapil.
It must be noted that Kuldeep's delivery which dismissed Fakhar Zaman was bowled at 80 km/h, higher than his average bowling speed.
It also worked against Australia. Although he did not get wickets, the flighted deliveries troubled David Warner from getting onto the backfoot and play.
Kuldeep seems to have found his mojo back, and if he could continue this, his success seems inevitable.
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