The national selection committee will have its task cut out as it would have to choose between Shardul Thakur and Jaydev Unadkat for the extra fast bowler's slot in the 15-member India squad for the World Cup, starting October 5.

As per ICC rule, every team has to submit its initial squad of 15 by September 5 but the final submission can be done by September 27, and a country is allowed to make as many changes as possible between the initial and final submission.

Interestingly, the Australia series ends on September 27, the day of the final submission.

Therefore, one shouldn't be surprised if India carry around 16 to 18 members for both the Asia Cup and Australia home series before zeroing in on the final squad.

So Unadkat and Shardul will certainly get their share of chances during the Asia Cup in Sri Lanka and the three-match home series against Australia (both in September), serving as a pre-cursor to the World Cup.

India's World Cup campaign against Australia starts in Chennai on October 8, which is exactly two months from this date, and the squad composition looks far from settled at the moment.

While the availability of injured batters KL Rahul and Shreyas Iyer would certainly make India one of the serious title contenders, it is the bowling combination on low and slow decks which will decide the team's run during the marquee event.

There are two bones of contention -- the extra seamer's slot and the third spinner's spot in the fifteen.

But, in the case of speed merchants, it wouldn't be as straightforward as one envisages.

Jasprit Bumrah is coming back from a lower-back stress fracture but even at 80 percent fitness, Bumrah will be playing the World Cup and so will Mohammed Shami and Mohammed Siraj.

With Hardik Pandya also filling up the fourth fast bowler's slot and is expected to bowl at least six to eight overs per game if not 10, the reserve pacer's slot becomes important.

In terms of performance and quality, Shardul is way ahead and has again proved his mettle in the Caribbean with eight wickets in three ODIs but Unadkat's advantage is being a left-arm seamer in this set-up.

With Arshdeep Singh, a left-armer with better skill-sets, shunted to the Asian Games T20 squad, Unadkat is very much in the scheme of things as he adds variation despite his lack of pace.

Also since the team management has carried Unadkat for so long, it is imperative that he is considered for the big occasion.

Another option is Bengal pacer Mukesh Kumar, who has impressed one and all with his work ethic but even he has been picked for the Asian Games in Hangzhou, which ends on October 7, provided India qualify for the gold medal match.

The third spinner's slot could be a more straightforward choice with Axar Patel miles ahead of Yuzvendra Chahal at the moment, although his skill-set is quite similar to Ravindra Jadeja, who is expected to start in all of India's games.

But Axar's better batting abilities and the team management's distinct lack of interest to try Chahal during the West Indies ODIs is an indicator.

Rahul might have to do 50-over simulation before Asia Cup ==================================== The Indian team management is desperate to get a fully fit KL Rahul during the upcoming Asia Cup in Sri Lanka but the senior Karnataka man, just like his pace bowling colleague Bumrah, will need to do 50-over match simulation ahead of the continental showpiece.

Closer to the World Cup, people in the know of things believe that if all specialist bowlers are fit and available, then it will be a straight tie-breaker between Mumbai's seam bowling all-rounder Shardul and Saurashtra's left-arm medium pacer Unadkat.

Having completed its round of experimentations during the three-match series against the West Indies, the think-tank won't cast its net any further and if sources are to be believed, they have zeroed in on the core 18-19 members for the World Cup, out of which 15 will be chosen for the tournament proper.

"The selectors and the team management wants to give both Rahul and Shreyas full chance of recovery. Rahul is certainly way ahead in terms of recovery and getting closer to full match fitness.

"But he needs to do match simulation where he is able to keep wickets for 50 overs," a BCCI source told PTI on the condition of anonymity.

"The Instagram videos show that he is doing well but 50 overs of keeping and at least 30 overs of batting in the heat will prove how his operated thigh is holding up in humid conditions.

"If he is able to do well over next nine possible games (six if India play the Asia Cup final plus three against Australia), it will be the best news for the Indian team," he added.

It is expected that India's Asia Cup squad will be selected end of this week or by the middle of next week (latest by August 16-17).

Likely core group: Rohit Sharma (captain), Shubman Gill, Virat Kohli, Shreyas Iyer, KL Rahul, Hardik Pandya (vc), Ravindra Jadeja, Mohammed Shami, Mohmmed Siraj, Jasprit Bumrah, Kuldeep Yadav, Surykumar Yadav, Ishan Kishan (wk), Axar Patel, Sanju Samson, Shardul Thakur, Jaydev Unadkat, Mukesh Kumar, Yuzvendra Chahal.

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