India will be without Ravichandran Ashwin for the remainder of the third Test in Rajkot after he was forced to withdraw immediately due to a family medical emergency.

Ashwin was at the heart of the action on Friday, scoring 37 (and being censured by the umpires for running on the pitch) to help India to 445 in their first innings, before becoming just the second Indian bowler to reach 500 Test wickets when he picked up Zak Crawley in the evening session. The 37-year-old gave a press conference during which he reflected on his joy over the “long journey” to 500 wickets.

A few hours later, however, the Indian management issued a statement revealing he had withdrawn from the squad.

“In these challenging times, the Board of Control for Cricket in India (BCCI) and the team fully supports Ashwin,” read a statement from BCCI honorary secretary Jay Shah.

“The BCCI extends its heartfelt support to the champion cricketer and his family. The health and well-being of the players and their loved ones are of utmost importance. The Board requests respect for the privacy of Ashwin and his family as they navigate through this challenging time.

“The Board and the team will continue to provide any necessary assistance to Ashwin and will keep the lines of communication open to offer support as needed. Team India appreciates the understanding and empathy of the fans and media during this sensitive period.”

Despite the request for privacy, the Indian MP Rajeev Shukla, who is also the BCCI vice-president, tweeted soon after that Ashwin had to leave Rajkot to be with his mother.

It is unclear the degree to which Ashwin can be replaced. While the use of a substitute fielder is certain, whether he could be replaced by a like-for-like player who could bat and bowl too is not. The laws of cricket, run by Marylebone Cricket Club at Lord’s, permit a replacement with the permission of the opposing captain. But the playing conditions for the World Test Championship are less clear on whether a player can be replaced once the game has begun for any reason bar concussion.

India are in charge of the Test, despite a strong fightback from England on the second evening led by Ben Duckett. They are two wickets down and trail by 238 runs. The withdrawal of Ashwin follows that of Virat Kohli, the great batsman, for personal reasons, while they are also missing Mohammed Shami, KL Rahul and Rishabh Pant through injury.

The series is finely-poised at 1-1.

Ashwin is the reason why India have become invincible at home

For all the void left by Virat Kohli’s absence, and the continued all-round excellence of Ravindra Jadeja, Ravichandran Ashwin’s withdrawal from the reminder of the third Test deprives India of their most valuable player of all. Ashwin is the single biggest reason why India have won 16 consecutive Test series at home.

‌One mark of a fine Test bowler is often considered taking four wickets per Test; in India, Ashwin alone takes six. With his mesmerising array of variations and mastery of accuracy, his off spins marries control with unerring threat, as 347 wickets at 21.3 apiece in India attest. He is also a terrific number eight, as England were reminded when his century in Chennai three years ago ensured India’s series victory.

With the bat, Ashwin has shown a particular relish for England’s spinners: his batting average of 27.6 at home soars to 38.8 when England tour.

‌Visiting teams in India fret about their team balance. An extra batsman or extra bowler? How to fit in both enough spinners while maintaining enough pace options?

‌Thanks to Ashwin and Jadeja, India have been immune from these concerns for the last decade. With the pair, India have always had two outstanding spinners – who spin the ball in different directions – in their top eight, and two men who have been picked as number six batsmen in Test cricket. Then, India have simply had to select their other three best bowlers, and been assured of a five-man attack, combining enviable batting and bowling depth.

‌Without Ashwin, India will now be denied this luxury. In some ways, Jadeja mitigates the loss; India are arguably better-equipped to playing half a Test with ten men than any other country. India still boast Dhruv Jurel, who has a first-class average of 46 and matched that number in his debut Test innings, at number seven and have four frontline bowlers. But their tail is newly vulnerable: Jasprit Bumrah will now bat at number eight.

‌Most significantly, India will now be without one of the best spin bowlers in the history of Test cricket. The upshot is that Jadeja and Kuldeep Yadav, the left-arm pair, will now be forced to bowl more. With little turn yet, the two were targeted on the second evening, leaking 75 runs from their combined ten overs.

‌The worries about the spinners, in turn, mean that India’s pace pair, Bumrah and Mohammed Siraj, will be summoned more. Before the Test, there were rumours that Bumrah would be rested. Instead, he has played, but gave indications of not being at full fitness in the last throes of day two. How Rohit Sharma deploys what remains of his attack looms as one of the greatest challenges of his captaincy, especially if Bumrah’s initial morning spell is kept at bay.

‌For England, the news about Ashwin has parallels with another terrific off spinner being unable to bowl after the second day of a Test: Nathan Lyon at Lord’s in June. When Lyon tore his calf, England had only lost one of their first innings wickets. After reaching 188-1, England were well-placed to clear Australia’s 416. Instead, three batsmen fell hooking within 40 minutes; the opportunity to exploit Australia’s misfortune was missed.

‌While offering Ashwin every sympathy, England will know that circumstances have presented them with an extraordinary chance to go 2-1 up in India. They might also consider whether to tweak their approach subtly, to ensure they maximise India’s time in the field – even if it means reining in their impulses a little, unlike at Lord’s.