Virender Sehwag, who smashed the fastest recorded triple century in Test history, said his sacking from the India team in 2007 fired him up.
"It hurt when I was dropped for the Tests against Bangladesh, England and Pakistan last year and I was motivated to prove myself," said Sehwag, who made an unbeaten 309 in the first Test against South Africa here.
"I wanted to prove I belong. I wanted to prove I was a good Test player. It made me even more determined to succeed."
Sehwag's stunning performance helped the hosts make light of South Africa's daunting first innings 540 to pile up 468-1 by stumps on the third day at the Chidambaram stadium.
When he reached 300 off 278 deliveries, Sehwag surpassed the previous fastest recorded triple ton from 362 balls by Australian Matthew Hayden against Zimbabwe in Perth in 2003-2004.
Only 19 of the 22 triple centuries in Test history have the number of balls faced recorded against them. Those that miss out are Garfield Sobers's 365 not out, Wally Hammond's unbeaten 336 and Hanif Mohammad's 337.
Sehwag hit 42 boundaries and five sixes in the second triple century of his career, having made 309 against Pakistan in Multan in 2004. No other Indian has achieved the feat even once.
The 29-year-old Delhi opener joins Australian legend Don Bradman and West Indian Brian Lara as the only batsmen to have crossed the 300-run mark twice in their Test careers.
Sehwag, who has four 200-plus scores in his 14 Test centuries, is well-placed to go after the retired Lara's record individual score of 400 not out when he resumes on Saturday.
"I am not thinking of the record right now, I just want to have a good night's rest," he said. "If I bat till lunch tomorrow I may get the record.
"But I have no words to describe how I feel. I have never concentrated so much in my life and that is why I think this one was better than the one in Pakistan.
"The hot weather is much tougher than what we faced in Multan. If we can get a lead of 150-200, South Africa will be under a lot of pressure against our spinners.
"But the wicket is still so good for batting that it is not easy to set a field for the bowlers."
Sehwag's double ton off 194 balls was the third fastest in Test history after New Zealander Nathan Astle's 153-ball effort against England at Christchurch in 2001 and Sehwag's own 182-ball innings against Pakistan in Lahore in 2006.
South African coach Mickey Arthur said he had not seen anyone bat better.
"We were beaten by a champion player," Arthur conceded.
"In my wildest dream I did not imagine that India will score so quickly and it all came down to one player.
"He played every possible shot in a disciplined manner and put India in a strong position. We tried every possible way to contain him, including bowling outside the line, but nothing worked.
"This is the best batting I have ever seen."