The left-hander has emerged the tournament's leading scorer with 580 runs in nine matches with three centuries.
Hayden is only the third batsman to have scored three hundreds in a World Cup after compatriot Mark Waugh and India's Sourav Ganguly.
"I think I am here today because my skipper believed in me and I believed in myself and it's as simple as that," Hayden said ahead of Wednesday's semi-final against South Africa.
Hayden had been struggling to find a place in the one-day side after his mediocre 2005 Ashes campaign, but made the most of the opportunities early this year to get the selectors' nod.
"You often rise to the occasion and I have been no different. This story is nothing remarkable," said Hayden.
"It's the story of what it means to us to play for our country and the level of expectation that we first put on ourselves and then the rewards for playing good cricket for Australia.
"It's no coincidence that this side is on top of its game for long periods of time. Like any player, I have had my fair share of ups and downs. Thankfully, I've stayed out of those lows, certainly they haven't extended."
Hayden said Australia had the best chance of winning the tournament if they maintained the momentum in the coming big games. Australia will complete a hat-trick if they win the final, having won the title in 1999 and 2003.
"We are a side which is at the top of its game and that gives you the best chance. Cricket is such a huge game with momentum and right now we have got so much momentum going into these final stages," he said.
Hayden has been instrumental in giving his team solid starts with Adam Gilchrist.
"I think throughout this tournament the sides that have got in trouble were those who lost early two or three wickets, so Australia's batting plan is try and develop a good platform and go from there," he said.
"I guess we are looking at how we can improve at this stage and that will start with the platform which Gilly and I, or our opening bowlers, create.
"We have played with great confidence and freedom. That has been part of our gameplan for a long period."
Hayden has emerged a strong contender for the player-of-the-tournament award, but said winning the title mattered most.
"I couldn't care less about player of the tournament. What we are here to do is to win the semi-final. If we win, then we go to the final and our objective will be to win the final," he said.
"I have been happy with the way we have batted as a unit, not just myself. Everyone of the top six has been outstanding and I am proud to be part of that. We have had some unbelievable achievements."
Hayden, who smashed the fastest Cup century off 66 balls against South Africa in a group match in St Kitts last month, said the Proteas could be the closest challengers to their supremacy.
"We admire their work ethic is similar to ours and the freedom with which they play is similar to ours. I learnt a lot from my first tour of South Africa in 1994 as there were some close games," he said.
"That was a baptism of fire for me, the one I enjoyed very much. I have enjoyed the competition with them and I enjoy it probably more against South Africa than any other side."