On the morning of day two, Bangladesh's bowlers did their job to take India's four remaining wickets and bowl the hosts out for 376. Hasan Mahmud was the star with the ball, finishing with figures of 5-83.

Bangladesh's hopes of getting off to a good start were dashed, though, as Jasprit Bumrah struck in the very first over to remove Shadman Islam with a peach of a delivery. Akash Deep then struck twice in two deliveries to leave Bangladesh three down inside 10 overs.

More: Hasan Mahmud creates Test history with five-wicket haul in Chennai

Captain Najmul Hossain Shanto was the next to go, caught by Virat Kohli off Mohammed Siraj. Bumrah took a second when he got rid of Mushfiqur Rahim.

Shakib came to the crease at 36-4, and was soon joined by Litton Das after Mushfiqur went. Bangladesh's star all-rounder caught the eye instantly – but not exactly with his batting.

Shakib appeared to be biting down on the strap of his helmet as part of a strange set-up, just as he faced the bowler. Closer inspection revealed that the strap was in place, and Shakib instead was biting down on some other piece of thread.

Why is Shakib @Sah75official playing with a strap in his mouth?@JioCinema @JioCinemaTweets pic.twitter.com/tIHXPZRjqH

— Kartik Verma (@krazzzykartik) September 20, 2024

Why was Shakib Al Hasan biting a string while batting?

Shakib let the cloth out of his mouth when he got to the non-striker's end, indicating that this likely had something to do with his routine only while the bowler is running up to him.

On the broadcast, Dinesh Karthik ventured an explanation for the strange routine, provided to him by Tamim Iqbal, a former teammate of Shakib's. According to Karthik, Tamim explained that it was a cue for Shakib to keep his helmet straight, i.e. facing the bowler, at least in his mind if not physically.

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It was clear to see that Shakib held the thread/cloth tightly in his mouth, with both ends disappearing down his shirt – one through the buttons and the other towards his left shoulder. However, it was still unclear where it had been tethered, possibly on his shoulder.

Report: Shakib’s new technique due to an eye condition

ESPNCricInfo reported Shakib himself has developed this new technique to maintain the correct head position while batting due to an eye condition, which surfaced in 2023. He is suffering from Central Serous Chorioretinopathy (CSC), in which fluid builds up under the retina, resulting in distorted vision.

BCB's chief physician, Dr Debashish Chowdhury, revealed that Shakib's new technique is in a testing phase.

"He has come up with this strap. It is completely his idea. It has not come from us. He is working on a way to hold his head position while batting. He was trying to manage this with a neck brace previously, so this strap thing is also in a trial-and-error phase. He has tried it in the nets. He has done a lot of shadows (shadow batting practice) with it too," Dr Chowdhury was quoted as saying.

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