Dhoni is not even half finished yet - Shastri

India head coach Ravi Shastri has dispelled doubts over MS Dhoni's future, stating that he is not even "half finished yet" and is very much in the management's scheme of things for the 2019 World Cup in England.

Dhoni has been in top form in the ongoing ODI series against Sri Lanka, scoring three unbeaten knocks of 45, 67 and 49, the last one coming in his 300th ODI on Thursday.

Shastri said that India were on the path of experimentation and rotation ahead of the next World Cup, but Dhoni, 36, remains firmly in their plans.

"MS Dhoni is a massive influence on the team. He is a living legend in the dressing room and an ornament to the game," Shastri said on Friday. "By no means or by any stretch of imagination is he finished or even half finished yet. If anyone thinks so, they are mistaken and they have another one coming. They are in for some surprises. The old dog has plenty to offer."

Apart from praising his batting skills, Shastri also lauded Dhoni as being the best wicketkeeper in the country.

"How do you pick players? When they are good, and Dhoni is the best limited-overs keeper in the country. Forget his batting stats, what else do you want. Just because he has played for so many years, you are thinking about a replacement?

"He is the best in the country. Would you look to replace Sunil Gavaskar when he was 36 years old or Sachin Tendulkar when he was 36? Dhoni is still the best in the business, so what is the need to even entertain those thoughts?" he asked.

Shastri underlined that experimentation and rotation will be the key going forward as India will play in excess of 40 limited-overs matches before the next World Cup. He endorsed the selectors' decision to keep fitness as the primary criteria for selection.

"ODIs are where we will experiment. Winning and losing will not matter so much. Of course, you play to win but we have to try all possible combinations. It is a long way to go until the World Cup and we want to take one series at a time.

"Most of our players have played in this series already, and the endeavour will be to rotate the players giving everyone enough opportunity, so that when we have 12-15 months to go for the World Cup, we have a nucleus of about 18-20 players in place. And we can then choose from this group just before the World Cup begins. Obviously, form will be important before that too, but the nucleus will be pretty much in place."

Reiterating his stand on fitness being the most important pre-requisite to selection, Shastri said no compromise will be made on the ground.

"We want the best fielding side on the park. That's it," he said. "So how do you become the best fielding side on the park? Fitness. And that's why there have been parameters set.

"My job is not to get involved in selection ever because I want my players to trust me. That's the job of selectors. They watch more cricket and they see it the year round. If anyone fits into their parameters, depending on their form, then on the cricket field, they are available for selection."

When asked if fitness parameters could see the likes of Yuvraj Singh and Suresh Raina being left out of World Cup plans, Shastri said, "When there are parameters put in place and that's the vision of the team, then everyone has to fit into those parameters. It is as simple as that."

Shastri's tenure as full-time coach began on a winning note for India, who won a second consecutive Test series in Sri Lanka and wrapped up the ODI series in emphatic fashion. He, however, has his sights set on the next overseas schedule that begins early next year, and said India have the potential to win all around the world.

"If you look at world cricket today, there is not one team in the world that travels well. Not a single one, but India can be that team. And we are already doing it bit by bit.

"If you look at last three years, we are starting to travel well. We won the ODI series in England in 2014. We whitewashed Australia [in the T20 series in 2016], and I don't even remember which team has ever done that in Australia. We have back-to-back series [wins] here in Sri Lanka. We won the Asia Cup last year. So this young side has already had a lot of 'firsts' overseas."

Shastri confirmed that Ishant Sharma will be travelling to the UK soon to join R Ashwin and Cheteshwar Pujara, who are playing out the last weeks of the County Championship. Shastri also said he would like to see more fast bowlers as well as top-order batsmen make their way to the county circuit, especially before the Test series in England next summer.

"I am all for that. Pujara, Ashwin and now Ishant is also going; I think he is joining Kent. These are vital and key players in our team. The more the players go, the merrier," he said. "I would like to see a couple more of fast bowlers going there. Zaheer Khan went there for a couple seasons to Worcestershire and he was a changed bowler. So I would love to see Umesh Yadav or Mohammed Shami going there, even if for short periods.

"And why just the bowlers, the batsmen should go too. If they want to before the tour, be it Virat Kohli, Shikhar Dhawan, Rohit Sharma or others, I am all for it."