Kings XI Punjab seamer Sandeep Sharma has said the Ranji Trophy was more difficult than the IPL for a fast bowler, and that it was a big step up from under-19 cricket.

"As and when you progress to senior cricket, Ranji Trophy cricket, every team has three-four quality seamers and quality batsmen. So Ranji Trophy cricket is more difficult than under-19 cricket, where there isn't much pressure or competition," Sandeep, who was part of India's victorious under-19 World Cup campaign in 2012, told ESPNcricinfo.

"I would say Ranji Trophy cricket is more difficult than IPL also, because Test is always more difficult than T20 or one-day cricket. And if you have to take four or five wickets there, you will have to bowl 20 overs or 25 overs, so it's a difficult job for a fast bowler."

Sandeep, one of the finds for Kings XI in IPL 2014 after having finished as their leading wicket-taker, had to miss India A's tour of Australia and the Champions League T20 last year with a stress fracture in his back.

He has returned strongly to claim 28 scalps, the most for a Punjab bowler this season in the Ranji Trophy, apart from a combined tally of 20 wickets in the Vijay Hazare Trophy and the Deodhar Trophy. In this IPL, he has dismissed seven batsmen*, at an economy-rate of 5.37, to be joint-highest on Kings XI's wickets' chart.

Sandeep, who will turn 22 next month, said coming back from injury was difficult. "I had done well up to that point, and was also included for the India A tour. But now I am back on track, and I have been bowling well in Ranji Trophy and IPL. So I am quite happy."

There has also been a marked increase in Sandeep's pace, which he puts down to a combination of a "balanced diet and hard training." "I was at the NCA when I was injured. I trained quite a bit at that point of time, hard training. I am [now] doing a lot of strength work at the gym, and with that, speed work also. Speed work includes doing a lot of short sprints and long sprints, and I stick to the diet chart. Proteins, Carbohydrates, fat… everything is there in the diet."

He also spoke about drawing from the experience of Mitchell Johnson, his Kings XI team-mate, when it came to training. "Obviously he has played a lot of international cricket, and he is among the top bowlers. I get to learn a lot from him, especially from a fitness point of view, on how to train hard. That culture has a positive effect on me.

"I keep saying this all the time that Johnson's bowling and mine are totally different, and I can't learn his bowling style. But a lot of chat revolves around the mental aspects: how to carry yourself on the field, how to prepare before match and how to handle pressure situations. For sure [I try to implement immediately something I learn]."

Some important advice, he said, came from Virender Sehwag. "He is a great man, and he teaches me a lot and shares his own experiences. I felt that the best advice I got was from Viru Paji," Sandeep said. "He always tells me I have been selected because obviously somebody thought I was good enough. He tells me: 'forget there is an international player at the other end, no matter however big a performer he maybe. A batsman needs just one ball to get out and you can deliver that ball.'"

Sandeep put a premium on the "mental side of things", and the importance of a quick turnaround. "Even if you have bowled three bad overs in T20 cricket, you still need to be focused for one more over, the fourth, because that one over can still turn the match around. You can be a hero.

"So I always think about the next ball and the next over. That will help you because T20 game is harsh on the bowlers, so it's important you carry yourself positively on the field."

Sandeep said the IPL had successfully bridged the gap between first-class and international cricket. "IPL is close to international cricket. Many bowlers I have spoken to tell me how IPL has helped them. They talk about how it's just the jersey that changes but the cricket remains pretty much the same [at the international level].

"In the IPL, a 20 or a 21-year-old boy gets to play in front of 50,000 people and when he goes on to play international cricket, he has already gotten used to big crowds and nervousness doesn't affect his performance.

"Also you find the same batsmen and bowlers who play at the international level playing in the IPL as well. When you have already done well against them, it gives you confidence that there is no reason you can't succeed at the international level."

*Statistics updated after Kings XI v KKR game on April 18

Arun Venugopal is a senior sub-editor at ESPNcricinfo