India have suffered a big setback ahead of the ODI and Test series against New Zealand, with Rohit Sharma ruled out of the remainder of the tour because of a calf injury.

ESPNcricinfo understands Sharma has a tear in his left calf muscle. The severity of the tear is not yet known, but it is likely that he will need a few weeks to recover.*

The injury took place when Sharma, leading India with Virat Kohli rested, was batting in the fifth and final T20I in Mount Maunganui on Sunday. He was on 54 at the time, and was treated on the field by the team's physio, but opted to continue batting. He hit a six, off Ish Sodhi, but was forced to retire hurt soon after, having reached 60.

Sharma is one of the primary openers across formats for India, and the selectors are likely to look for his replacement(s) in the India A contingent, which is currently playing a four-day series against New Zealand A with the likes of Prithvi Shaw and Shubman Gill in their ranks.

India's Test squad hasn't been announced yet, but they have already lost two players to injury, with Sharma's pulling out coming on the heels of Hardik Pandya being ruled out.

The three-match ODI series against New Zealand starts on Wednesday in Hamilton, followed by matches in Auckland and Mount Maunganui. The final leg of the Indian tour, comprising two Tests, will commence on February 21 in Wellington and move to Christchurch, where the second Tests starts on February 29.

Sharma will rue the timing of the injury, coming as it did at an important moment in his career. He was on the verge of making the Test debut in 2010, but an ankle injury on the morning of the Test in Nagpur pushed back that moment by three years. Two years back, Sharma acknowledged that he had to make peace with himself and just cash in as and when opportunities came, without worrying about Test selection anymore.

He did cash in big time after being selected as a Test opener in India's last home season, which featured South Africa and Bangladesh. Till yesterday, Sharma trailed Virat Kohli by just 46 runs, with the pair occupying the top two slots among the highest run-makers for India across all formats since the start of 2019. In this period, Sharma has the most hundreds - 11 - compared to Kohli's seven, including the five during the 2019 World Cup, the most by a batsman in a single edition of the competition.

Against South Africa, opening for the first time in Tests, Sharma scored twin centuries in Visakhapatnam and followed that up with a double-century in Ranchi, cementing his opener's slot in the process.

Shubman Gill led India's fightback with a double-century Getty Images

Who will be the replacement?

The latest update means Sharma's 20-year-old Mumbai team-mate Shaw will eye an ODI debut after being named as the replacement for the injured Shikhar Dhawan. That return capped Shaw's resounding comeback from a ban following a doping violation last year, a double-century against Baroda in the Ranji Trophy and then 150 in his first match upon landing in New Zealand against New Zealand XI in January the highlights. Shaw had scored nearly half of India's 372 with the next best being Vijay Shankar's 58 in that match.

The bigger question for the selectors and the Indian team management is to find a suitable opening partner for Mayank Agarwal, who himself had a torrid last week getting a pair in the first of the two first-class matches against New Zealand A.

KL Rahul would have been in contention for the third opener's slot along with Shaw and possibly even Gill. But his massive dip in form between 2018 and 2019 in the format eventually prompted the selectors to drop him ahead of the home Test season in 2019. MSK Prasad, the chairman of selectors, called Rahul an "exceptional talent", but said despite having been given an extended rope as Test opener he was "not delivering consistently, and only delivering in patches".

With Shaw out at the time, the selectors decided to instead include Gill in the Test squads against South Africa and West Indies after the Punjab batsman raked in the big runs consistently in 2019. Gill, who had expressed disappointment earlier after not being selected for the West Indies tour, made his India debut in an ODI series in New Zealand last year, featuring in two matches, but those did not go as well as expected.

On the India A tour of West Indies, he finished as the top run-getter in the ODI leg. He followed that with an unbeaten 204 off 248 balls against West Indies A in an unofficial Test after India A were reduced to 50 for 4 in the second innings.

On Sunday, he hit another double-century, this time in another unofficial Test, against New Zealand A, to once again announce his form and intent.

The other contender remains Shaw, who made his Test debut with a century against West Indies in 2018 at home, but injuries and the doping ban have meant he has spent more time at the National Cricket Academy in Bengaluru than with the Indian team.

With the New Zealand Test series part of the World Test Championship, the selectors and team management would want the best batsmen to take the field. What makes their job difficult is Rahul, who finished as the Man of the Series in the 5-0 T20I whitewash, has been in good form, as are Gill and Shaw.