Rohit Sharma's century against South Africa in Southampton was the slowest of his ODI career. Yet, the timing, the composure and the manner in which he scored his runs prompted his captain Virat Kohli to label the century Rohit's "best ODI innings".

It is a significant statement by Kohli. Rohit has scored several centuries, including three double-tons, so what makes this one so special?

First up, Kohli said, there was the pressure of playing in the World Cup, and then the pressure of India needing to win their tournament-opener, in a format where each of their nine league matches will carry equal significance. "In my opinion this is by far his best ODI innings because of the kind of pressure the first game brings from a World Cup point of view," Kohli said at his post-match media briefing.

According to Kohli the goal set for the top order, comprising Rohit, Shikhar Dhawan and himself, was for one of the three batsmen to anchor the innings, bat deep, and build partnerships. After Dhawan and Kohli fell early, Rohit had to carry that responsibility.

The target was not steep, but the bounce was. South Africa fast bowler Chris Morris said there was "something in the pitch", which India's quicks, led by Jasprit Bumrah and Bhuvneshwar Kumar, exploited well. Even Hardik Pandya got one of his hard-length deliveries to climb awkwardly and hit Faf du Plessis' gloves.

"He [du Plessis] said it was like facing the first hour of a Test match," Morris said.

Kagiso Rabada and Morris attacked India's top order, bowling tight lines and pushing them on the back foot with good hard lengths. Rohit was lucky more than once to get away with balls pinging off his edge and gloves and landing away from the reach of the fielders.

Keeping the mounting challenge in mind, Rohit still managed to keep his head. "As a batsman when you go in and a few balls bounce like that, it is not easy to gather yourself again and play in a calm manner." Kohli said. "A lot of times batsmen tend to hit their way out of the situation. But he was very composed, he was very - he's played so many games, we expect a lot of maturity and a lot of responsibility from someone like him."

Even Rohit agreed that it was an atypical batting performance. "I couldn't play my natural game," Rohit said to the host broadcaster. "Certain shots that I love to play, I had to cut down and make sure that I play close to the body. I had to try and leave as many balls as possible in the initial spell. It was not a typical Rohit Sharma innings."

Rohit now is joint fourth among ODI centurions in chases. Kohli, who tops that list, said Rohit played the "perfect" innings. "In my opinion, of all the brilliant innings I have seen him play, I think this, for me, was the top of the pile because of the way he compiled his innings, and at no stage did we feel like, or he felt like he is going to throw it away.

"I think controlling the game so beautifully from one end and allowing the others to display themselves and string in small little partnerships, looking at the fact that they were only chasing 228, he played the perfect innings for that kind of a situation, on that kind of a wicket, against a bowling attack that was threatening to pick up wickets at any stage. So, yeah, in my opinion, by far his best knock."