Rory McIlroy has described his final-round collapse at the 2011 Masters as the "most important day of his career".

McIlroy, now golf's world No.1 and aiming to complete the career grand slam at Augusta National next week, led by four shots going into the last day but dropped six in three nightmarish holes to end up with a round of 80.

However, speaking to the BBC, Northern Irishman McIlroy revealed that chastening experience set him up for major wins at the US Open in 2011, the US PGA in 2012 and 2014, and last year's Open at Royal Liverpool.

"I learned so much about myself and what I needed to do the next time I got into that position," he said. "If I had not had the whole unravelling, if I had just made a couple of bogeys coming down the stretch and lost by one, I would not have learned as much.

"Luckily, it did not take me long to get into a position like that again when I was leading a major and I was able to get over the line quite comfortably.

"It was a huge learning curve for me and I needed it, and thankfully I have been able to move on to bigger and better things.

"Looking back on what happened in 2011, it doesn't seem as bad when you have four majors on your mantelpiece."

If McIlroy does claim his first green jacket next week, he will join an elite group of just five players to have won all four majors - Tiger Woods, Gene Sarazen, Ben Hogan, Gary Player and Jack Nicklaus.

And as favourite to seal victory on the Georgia course, the 25-year-old admitted failure to win the tournament at some point in his career would haunt him for a lifetime.

"If I was to look back as a 60-year-old at my career and had not won a green jacket I would be very disappointed," he added. "It is the only one left and it is a course I feel I can do well at. I feel I could win multiple times, but getting that first one is the most important thing.

"Winning all four majors means you are a complete player. I can achieve something special."