Mayank Agarwal makes a not-so-easy innings look easy

Sometimes, you need a flat pitch to show off your full range of shots. Mayank Agarwal may have been batting on 85, but at the same score in South African conditions, he probably wouldn't have played this shot off Vernon Philander: a front-foot late-cut to a short-of-good-length ball that was curving gently away from him, wide of off stump.

It was all hands and wrists, and the gully fielder, placed for that sort of shot, fell resignedly to his right as the ball sped past.

On Indian surfaces offering more turn and bounce, Agarwal may not have looked to reverse sweep Senuran Muthusamy from the rough outside his leg stump, but he did it with ease on this Visakhapatnam pitch.

By his own admission, Agarwal doesn't play the reverse sweep all too often, but he played it three times on Thursday, square and fine, nailing each of them.

"When I played the reverse sweep, the thing that [Rohit Sharma and I] were talking about was that I don't really reverse sweep and we were well set," Agarwal said during his end-of-day press conference. "We were quite happy with the way we were batting and [it was] good that we were able to manipulate the field. They had started to bowl on the pads and it was nice to get a couple of boundaries so they can shift around players, and we were talking about more ways how we can get runs. Risk-free runs."

Pretty much all of Agarwal's 215 runs - save the few during a tricky first half-hour on Wednesday against the new ball - seemed risk-free, even those that came off the shots described above, or off his numerous inside-out drives and lofted hits. There was a sense of certainty about when he chose to play what shots and how he executed them. He did this for close to eight-and-a-half hours and ended his innings with a control percentage of 90.

While this reflected the conditions he batted in, it was still some achievement for a batsman in only his fifth Test match to show such authority over such a long period of time, in sapping humidity, while trying to bat proactively and put the bowlers under pressure. It was Agarwal's first Test hundred, but at no point did he seem like he was learning how to make one. He just seemed to know, already.

Agarwal took years to gain that knowledge. Before the start of the 2017-18 domestic season, he only had two hundreds from 29 first-class matches, and an average of 38.19. That sort of record is pretty handy in certain countries, but not in India, where batsmen who get called up to the national team routinely average in the high 50s or even low 60s.

Something clicked into place in November 2017, when Agarwal made these scores for Karnataka, in back-to-back innings: 304*, 176, 23, 90, 133*, 173, 134. Since that season, Agarwal averages 62.50 in first-class cricket. There have been two more double-hundreds, one against South Africa A last year in Bengaluru, and now against a South Africa side featuring some of the same bowlers.

That transformation must have required work on all aspects of his game, but the one Agarwal picked out after his innings in Visakhapatnam was learning to handle the physical demands of batting for long periods.

"For me, a lot of long-distance running has helped me, and also, when I was training before that season with my coach RX [Muralidhar] sir, we made sure that we bat five-five, six-six hours. We had gruelling sessions and would make sure that I would bat two hours to two-and-a-half hours, then take a little break, and then bat [again]. So it is just preparing in that manner, preparing to play those long hours, which has helped me, combined with a lot of long-distance running."

All that running, all that batting, was part of the hidden substructure beneath Agarwal's 215. It may have looked absurdly easy at times, but at no point was it actually so.