Root's century is his 31st in Tests and a record 10th against India. He also bettered Sir Alastair Cook's previous England record with his 91st score of fifty or more in the format.

On what looks a challenging pitch for batting in Ranchi, England were earlier reduced to 112-5 after Ben Stokes (3) was pinned lbw on the stroke of lunch by a Ravindra Jadeja (1-55) delivery that barely bounced above ankle height.

But with Root leading the rebuild, sharing in a 113-run partnership with Ben Foakes (47) and an unbroken 57-run stand with Ollie Robinson (31no), the visitors will feel very content with their day's work after winning the toss and opting to make first use of the surface.

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Root was muted in his celebrations as he brought up his hundred inside the final seven overs of the day, leaving his skipper Stokes to the lead the fist-clenching and hand-clapping on the England balcony.

India fast bowler Akash dazzles on debut

India debutant Akash Deep (3-70) had earlier ripped out the England top order, taking three wickets in a devastating maiden spell in Test cricket.

Akash picked up Ben Duckett (11) - caught behind off a beauty from round the wicket - and Ollie Pope for a duck in the same over, the latter perhaps slightly unfortunate to be given out on DRS when getting a big stride in to the 27-year-old fast bowler.

Zak Crawley was then bowled for 42, albeit not quite as comprehensively as he was in the fourth over of the day when his off stump was sent cartwheeling out of the ground - Akash made to wait for the wicket after overstepping for a no-ball.

Crawley threatened to make the most of the reprieve, smashing 18 runs from four balls - including a glorious six struck over long-on - off the contrastingly wayward Mohammed Siraj at the other end as he, and England's opening stand, neared the half-century mark.

However, their momentum was forcefully halted with Akash's triple salvo in the space of two overs as India finally made inroads on the hugely helpful surface early on.

Root first found a willing partner in Yorkshire pal Jonny Bairstow (38) as the pair put on 52 prior to lunch. It was a stand dominated by Bairstow, who cracked four boundaries and a six in his 35-ball knock before succumbing lbw to Ravichandran Ashwin (1-83) when attempting one sweep too many.

It was Ashwin's 100th wicket against England in Tests. The 37-year-old off-spinner took the 500th for his career in the previous Test in Rajkot.

Both Pope and Bairstow fell to successful India DRS decisions but the hosts also lost two of three reviews for the innings on a couple of close shouts against Root - to his first ball, when struck outside the line by Akash, and in Jadeja's over immediately after Ashwin's breakthrough, with a thin inside edge saving him.

There would be no doubt about Stokes' dismissal in Jadeja's next over, however, as his delivery scooted along the deck to deceive the England skipper and pin him lbw to the last ball before lunch.

Root finds stellar support in Foakes and Robinson

At that stage, England appeared in danger a subsiding to a below-par score, only for Root and Foakes to dig in and stubbornly see out the entire afternoon's play - the first time in the series that the visitors have not lost a wicket in a session.

And it passed without any great alarm too, in stark contrast to the morning, with India burning their final review in desperation to a hopeful lbw appeal from Jadeja against Foakes that was sliding down leg.

Foakes kicked on after tea and seemed set to join Root through to fifty as he slog-swept Ashwin for six and a pair of boundaries in the same over. But the sudden surge seemed to disturb his rhythm as the returning Siraj (2-60) picked him up in the next, tamely chipping one to short midwicket.

Tom Hartley (13), as has become a habit through the series, played some nice shots in a sparkling mini cameo before he was bowled by a ripper from the much-improved Siraj, who began to find some reverse swing in his second spell.

But Robinson batted responsibly through to stumps, providing stellar support to Root that allowed his partner to reach a richly-deserved hundred shortly before the close.

Crawley: We never doubted Root

England opening batter Zak Crawley:

"We're chuffed for Root, we never doubted him.

"We fully expected him to go out and get runs in this game, he's just a phenomenal player, one of the best, if not the best player for England.

"Those boys played unbelievably well. When I got out, I said if we got anything above 300, we're ahead of the game and I stand by that."

Follow text commentary of day two of the fourth Test between India and England live on skysports.com and the Sky Sports App from 3.45am on Saturday (4am first ball).

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