Rohit Sharma reached his fifth ODI century with a single to deep square leg. He raised his arms, pointed to the sky and went down on his knees to complete an extended celebration. He was soon driving his 25th four of the innings to the deep extra cover rope to become the first man in the world to make two ODI double-centuries. This time, the celebration was a roar that went on and on. Both celebrations spoke not only of the landmarks, but also in what context they had been achieved, and how important they were for Rohit.

Rohit's timing with injuries has been as bad as it is good with the bat. He hurt himself on the morning of what would have been his Test debut in 2010, and had to wait three more years for another chance. Then, on successive tours to England, in 2011 and 2014, he got injured again. This August, Ajinkya Rahane replaced him against England and made his maiden ODI century. Even as whispers grew about whether Rohit should drop down to the middle order on comeback, he kept saying that it was opening that got the best out of him.

When asked in an interview whether there was a healthy rivalry between him and Rahane now for the opening slot, Rohit retorted by asking whether the same question was put to Sachin Tendulkar on his injury comebacks. The opening slot has made Rohit. No wonder he is so keen to retain it. No wonder that roar lasted so long.

Rohit Sharma's last eight innings in completed ODIs at home have included two double-centuries, one big hundred, and two half-centuries at an average of 113. Since the start of 2013, when he was moved up to open, Rohit has made 1765 runs in 38 innings at 53.48. For openers with at least 1000 runs, only Hashim Amla averages more in the history of ODIs. Before 2013, he had a middling average of 30.84 which has now shot up to a very respectable 38.19.

This was Rohit's first international match since August, when he broke his right middle finger in the second ODI against England. It was only around October 20 that he started batting again in the nets, wrist taped heavily. For about a week or so, he could not sense the ball properly on bat.

But when he scored 142 off 111 for India A against the Sri Lankans in the warm-up game in Mumbai, things fell into place. There was still a need to guard the finger while fielding, but the feel had returned with the bat.

Feel is crucial for an instinctive, flowing batting style such as Rohit's. It didn't seem to be with him at the start at Eden Gardens, when he was on 4 off 16, and Rahane was cracking boundary after boundary at the other end. "I am coming back after an injury so, I will be a little nervous to see how I bat," he had said.

Then he charged out at Shaminda Eranga and was dropped at third man. He wasn't giving another chance till he had gone past the double.

He got to his 50 off 72 deliveries, 100 off 100, 150 off 125, 200 off 151 and 250 off 166. The Bangalore double had been a late explosion of sixes - 96 of his 209 then had come that way. This was a case of a batsman who had found his touch immediately on comeback, and was just refusing to give it away with a rash shot, his desire to reclaim that opening position an added motivation. After he went past hundred, there was a kind of inevitability in Rohit's approach that told you this was going to be a really, really big one.

To bat more than 18 overs till the end of the innings after you have reached your hundred in a one-day match requires some application, and fitness. Even as his boundary count and strike-rate was going berserk, there was still a certain safety to Rohit's game. There were no high-risk strokes like reverse-sweeps or scoops.

He kept exploiting the field intelligently throughout his innings. When there was no deep midwicket, he swung safely in that direction. When there was no sweeper, he lofted repeatedly over cover. When there was no mid-off, he lofted cleanly down the ground. He made sure he hit the gaps with his drives and cuts.

"I have worked on the mental aspect (during the injury break) and that will hopefully help me not just for the next five months but the next five years," Rohit had said. At this rate, an ODI triple-hundred does not seem impossible any more.

Abhishek Purohit is a senior sub-editor at ESPNcricinfo