With Gopichand's thirst to do better, India can be sure that he would be working towards a Golden dream at Rio, courtesy PV Sindhu in the semi-finals.

One day, ten months ago, Pullela Gopichand read out the riot act to PV Sindhu. He told her that unless she screams standing in the middle of the badminton court at the Pullela Gopichand Badminton academy in Hyderabad, with 50-odd shuttlers and coaches looking on, he would not let her touch the racquet.

"It was very tough for her because she is a soft person and not very aggressive,'' said PV Ramana, Sindhu's father, who was present when the incident happened. Ramana, who was a member of the bronze-winning Indian volleyball team at the 1986 Asian Games, understood the reason behind Gopi's insistence.

"Gopi says Indian children grow up in a very protected environment because of which they do not express themselves enough, even when they are in a sports arena. Showing a temperament by screaming a bit and an aggressive body language also helps to intimidate the opponent. In sport, where domination is key, this aspect is important,'' Ramana said.

Sindhu was driven to tears, but at the end of what seemed to her like an ordeal, she did scream, standing alone in the middle of the court.

Off court, Gopichand is perhaps the most genteel person you will meet. It is his mind that is tough as steel. 'Grit' could well be his middle name.

"When I started out as a coach, there were many who dissuaded me saying the system will not let you succeed. But I feel it is important to keep pushing. I saw ourselves as world beaters and I wanted to prove the sceptics wrong,'' Gopichand told me a year ago.

Resting on his laurels as a former All-England champion would have been the easier option for Gopi, but the desire to be part of world badminton, a space he calls "an exciting place to be in", propelled him into the role of a coach.

A self-taught guru, Gopichand is considered one of the most tactically astute minds in the game today. One who made Indian shuttlers, hitherto tourists on the badminton circuit, believe that the Great Wall of China, the badminton powerhouse, could be breached.

Sindhu's victory in the women's singles quarter-finals of the Rio Olympics on Tuesday, over Wang Yihan, the world number two and the silver medallist at the London Olympics, is the result of that "You can do it'' mantra. Never-easy-to-please Gopi was in fact, happy with the 21-year-old's work ethic against a better-ranked opponent.

"It was a spirited performance. Both players fought like hell but Sindhu stayed calmer under pressure. It is good to see her perform like this at this stage,'' said Gopi, after Sindhu's quarter-final triumph. He believes that in the form she is in now, she is good to go for gold.

It also helps Sindhu's cause that she is not running into either Spain's Carolina Marin or China's Li Xuerui in the semi-finals. Sindhu will fancy her chances against Japan's Nozomi Okuhara, the world number six – even though with a 3-1 win-loss record against Sindhu, she has the edge on paper. The Indian's sole win came in 2012, while Okuhara has got the better of Sindhu in 2014, 2015 and February 2016.

Gopi and Sindhu beat the sun six days of the week. Both reach the academy by four am for an intense session that lasts three hours or more. The jugalbandi focuses on strategies to surprise opponents and works out chinks in Sindhu's armour. Gopi divides the court into different parts and works on Sindhu's wristwork, to get that backhand flip from the far left corner of the court to the right. Or the lunge at the net to execute that perfect heart-stopping drop shot.

Getting a ringside view into a world-class badminton coach training a world-class badminton player is like attending a science class. It is watching an astute mind unravel a difficult game and plot to gain complete control over the bird, its flight, its speed and its landing, by applying just the right pressure of the hand and the racquet.

Those lessons are being put into practice at Rio. To Sindhu's credit, she did not let the occasion, the stage and the fact that it was her debut at the Olympics get to her. Her reputation as a giant killer preceded her and she showed that those earlier two victories over Wang Yihan were not a flash in the pan. It was an extremely tight game but Sindhu switched gears to smash her way to victory at just the right moment.

"It is not finished yet. There is still a lot of work to do,'' said Sindhu after the match.

That could well have been Gopichand speaking. When I asked him what does every medal won by his wards mean to him, he replied "more responsibility''. "It tells me there is a lot of work yet to be done. When someone wins a medal, I tell myself we need to better it next time,'' said Gopi.

At the Sydney Olympics in 2000, a dejected Gopichand, after losing in the pre-quarters, told fellow shuttler Aparna Popat, "I do not know if I shall be able to compete in the next Olympics but I would like to coach someone and bring home an Olympic medal through them.''

Gopi realised that dream through Saina Nehwal's bronze at the London Olympics. Knowing his thirst to do better, India can be sure that Gopi would be working towards a Golden dream at Rio, courtesy Sindhu.