The 26-year-old, playing in his first Test, after featuring in as many as 108 ODIs, grabbed the opportunity to showcase his credentials in the longer format with a resolute innings.
The Mumbai batsman, in the process, became the 14th Indian, the second this year after Shikhar Dhawan, who scored 187 against Australia at Mohali, and 96th batsman overall to score a century on debut in the five-day game.
At stumps, the home team was well-placed on 354 for 6 (from 102 overs), leading the visitors by 120 runs.
Rohit was unbeaten on 127, his innings studded with 16 hits to the fence and one over it. Giving him company at the end of the day was R Ashwin, on 92, the duo having put together 198 runs for the seventh wicket to help consolidate the home team’s advantage.
Earlier, Shane Shillingford ripped though the Indian top order to wrest the initiative for the West Indies in the day’s opening session.
The 30-year-old off-break bowler picked four wickets, including the scalp of Sachin Tendulkar (10), as the much-vaunted Indian batting line-up suffered a spectacular collapse on a fast deteriorating Eden wicket.
Rohit and Ashwin, however, ensured a complete turnaround in the third session.
Morning session: (83 runs, 27 overs, five wickets)
Shillingford, who started the proceedings for the visitors on the day, struck in his second over, inducing an inside edge from Shikhar Dhawan's (23) blade that crashed on to the stumps.
A few overs later, Shillingford struck again, having Murali Vijay stumped for 26. The batsman was guilty of recklessness at a time when no aggression was required.
It was Shillingford's 50th Test wicket in his 11th match.
And it saw the arrival of Sachin Tendulkar to a rapturous welcome. The Master Blaster began with a couple of well-timed boundaries off Shillingford.
Cheteshwar Pujara (17) too started off well, with a boundary apiece off Shillingford and debutant Sheldon Cottrell. However, a moment of indecision cost him his wicket.
A rising 144 kph delivery from Cottrell had Pujara in two minds, to play it or leave. He decided to hit it over the wicketkeeper, but only succeeded in guiding it to his gloves, giving the bowler his first Test wicket.
Then Shillingford struck for a third time. And this time it was the prized scalp of Tendulkar (10).
Replays suggested the ball struck the Master Blaster high on the pad and definitely did not merit a leg before decision. Umpire Nigel Llong thought otherwise.
Tendulkar’s stay at the crease, in his 199th Test, lasted all of 41 minutes.
The bowler picked his fourth wicket in the next over, having Virat Kohli (3) caught at short leg by Kieran Powell. Umpire Llong did check for a no-ball but the batsman had no luck there as well.
At lunch on the second day, the home team was 120 for five in 39 overs, still 114 runs off the visitors' first innings score of 234.
Post-lunch session: (109 runs, 29 overs, one wicket)
A single by Dhoni, in the fifth over after resumption, off Darren Sammy helped raise the 50-run partnership for the sixth wicket.
It was a vital partnership, considering the context of the game, and the duo involved in it needed to continue for the home team to harbour any hopes of taking a lead.
Unfortunately for India, it was not the case; a change of ball in the 52nd over did the trick for the West Indies. Tino Best struck with his first delivery, having Dhoni caught behind for 42.
His 63-ball knock was inclusive of five boundaries; he added 73 runs for the sixth wicket with Rohit.
In came Ashwin and he provided Rohit the support the debutant required, the latter proceeding to complete a well-deserved half century with a boundary off Permaul.
A couple of overs later, when Ashwin steered Permaul to the fine leg boundary, it brought up the 50-run partnership for the seventh wicket.
Having lost five wickets with just 83 runs on the board, the home side had inched close to the visitors’ first innings total courtesy these two partnerships.
Post-tea session: (125 runs, 34 overs, no wickets)
It took India just seven balls after resumption to take the lead, successive boundaries doing the trick. Rohit first hit Permaul to the fine leg fence to help level the scores.
A splendid cover drive by Ashwin off the first ball of the next over (by Sammy) ensured the advantage was retained following the stutter in the morning session.
The 27-year-old took a single off Permaul to bring up his fourth Test fifty and hit a boundary a couple of balls later to raise the 100-run partnership for the seventh wicket. The gritty partnership ensured India the lead.
Rohit’s century was the next thing on the agenda. And the batsman reached three-figure mark in style, with three successive boundaries (off Cottrell), the second of those ensuring both his century and helping his team get past the 300-run mark.
And he found a perfect partner in Ashwin.
The 27-year-old off-spinner, who already has a Test ton against the West Indies to his name, will complete a second when he comes out to bat on Day Three.
Image: Rohit Sharma celebrates after completing his century.
Photograph: BCCI
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