"For the first time in my life there have been claps in a press conference. I am sure this is a special moment for me, guys." Yuvraj Singh made a telling opening statement. The whole media room was in splits. For the next 17 minutes Yuvraj played the role of entertainer effortlessly, his answers laced with wit and charm.

It was difficult to imagine the man sitting there as the same one who had fought doubts, conditions and the formidable Australian fast bowlers and stood tall and strong for one-and-a-half hours to eventually take India into the semi-finals. Still, it was not entirely a surprise; Yuvraj has now been named man of the match in four of India's seven matches so far this World Cup, so he must be getting used to it.

"I've been batting really well since the England game," Yuvraj said. "The plans are working for me: trying to work till the end, trying to hit the ball down the ground into the gaps. I just kept telling myself to bat till the end, stay till the end."

With 12.3 overs left, 74 runs required and just one specialist batsman in Suresh Raina for support, Yuvraj was left to hold the Indian innings together and take it past the finish line. The Aussies were steadily closing in, having picked up the wickets of Gautam Gambhir and MS Dhoni in quick succession.

Yuvraj had come up with an all-round performance in India's 80-run victory against West Indies last Sunday. His 113 in that match was his first century since June 2009. It was a knock of determination, as he fought hard to stay on his feet in the Chennai heat while suffering from dehydration; he even threw up a few times while batting. Later in the evening he returned to pick up two wickets to expedite the Indian victory.

Even in the earlier matches in the tournament, he had restrained his attacking instincts admirably to stay put, and brave India through tense moments in victories against Ireland and Netherlands after the main batsmen had lost their way easily. Coming into the quarter-finals, Yuvraj had run the whole gamut of experiences, which only helped him survive the high-pressure situation at Motera, which he said had drained the players both mentally and physically.

On Thursday, he turned up match-fit and was one of India's best bowlers with two top-order wickets and followed it with an unbeaten 57, an innings he described as one he had built in his dreams exactly a year ago. "The emotions, I really can't explain them, because it was tough out there. From last year I have been dreaming of playing Australia in a crucial game. I don't know why Australia; probably because they are three times world champions. I'd been thinking about this moment for the last 365 days and it actually came true. I just believed in myself, I envisioned that moment from time to time: me staying there till the end and hitting the winning runs for India. So it is a very emotional moment for me."

There were a few jitters, especially the child-like indecisiveness between him and Gambhir while going for tight singles. Gambhir fell victim to one such moment of confusion and was run out. Yuvraj accepted his role in the mix-up. "It was a bit of a mishap with Gautam. We haven't batted too much together and the running between the wickets was just out of order. And I think it was my mistake and I apologise."

It was not an isolated incident, as there was immense pressure on both teams. Experienced hands like Brett Lee failed to come through when Yuvraj and Raina began turning the screw on the Australians, at the start of the final eleven overs of the match. Lee had taken the wicket of Dhoni in his previous over, but in the 40th, the pair took him to the cleaners, with Yuvraj hitting two scorching boundaries.

In the next over, Shaun Tait was wayward and gave away 13 runs. Those two overs proved to be one of the catalysts of India's win, but Yuvraj said it was not a planned counterattack. "It was very difficult to control the emotions because the heartbeat was racing in the pressure situation. If we made one mistake in a situation like today we would be out of the World Cup. Various thoughts run through your mind, but I decided that I would only watch the ball, keep it simple and as far as possible not hit in the air. Unless the asking rate peaked to seven-and-a-half, only then I would go for the big hits; till then I would hold back."

Yuvraj revealed that there was a driving force behind his recent success, a person he will unveil if India make the final on April 2. "I am playing this tournament for a special person. That special person always comes into my mind whenever I am in a pressure situation. Hopefully it will work out in the end."

Not only was he a bit secretive, he even turned philosophical about his good work against Australia. "You have a lot of thoughts [in the mind while batting] but whenever you want to desperately do it for your country and your team it somehow works out. It is great it is working at the right moment in the World Cup. It is a great victory for us."

Yuvraj had planned for every eventuality. On the eve of the match, he was the last batsman to face throwdowns from coach Gary Kirsten. Yuvraj knew the Australians would fire a lot of short-pitched stuff at him to unsettle him. "I just wanted to concentrate on hitting everything down the ground while leaving out the short balls."

That planning came to fruition on Thursday. He checked his shots and emotions till the victory stroke was unleashed. Once the job was done, he came crashing and sliding down on his knees, the way football players rush to the flag after scoring a goal. Then he let out a victory roar. A little later, he trotted out the jokes.

Nagraj Gollapudi is an assistant editor at ESPNcricinfo