Rory McIlroy completed his meteoric rise from golf's boy wonder to World Number One - and stopped Tiger Woods from possibly pulling off one of his most remarkable wins.
Needing to win the Honda Classic in Florida to end Luke Donald's nine-month reign, the 22-year-old from Northern Ireland had to contend with Woods, joint 18th teeing off, charging from nine behind to only one back.
An eight under par 62, one outside the course record, was the lowest final round of the American's career and it came to a crescendo when he followed a 24-foot putt for birdie on the short 17th with an eight-footer for his second eagle at the last.
That was just like the good old days for Woods - and it came moments after Lee Westwood had equalled his lowest score in the States with a 63.
All eyes then turned back to McIlroy and he was up to the task as he became the second youngest World Number One - after Woods - since the Rankings began in 1986.
The US Open Champion had just had his first bogey of the day on the 12th to be 11 under par to Woods's ten under, but he came straight back with an eight-foot birdie on the next.
McIlroy then saved par from deep rough beside the 14th green, but still to come was the three-hole stretch known as the "Bear Trap".
Ahead of him Justin Rose went into the water on the short 15th and fell out of contention, but McIlroy got up and down from the back bunker there and then did it again at the 190-yard 17th.
That took him to the tee on the 556-yard last still two in front and he made the safest of pars for a closing 69 for a 12 under par total of 268 that gave him the title by two from Woods and 43-year-old American Tom Gillis, with Westwood two strokes further in back after starting the day 27th.
Charl Schwartzel finished a further shot back on seven under par alongside Justin Rose after closing rounds of 69 and 70 respectively while Graeme McDowell also finished in the top ten after finishing his week off with a 69.
But the day was all about McIlroy's rise to the summit of world golf after claiming his third US PGA Tour victory.
He won at Quail Hollow in 2010 with a closing course record 62 and then last June, of course, was the youngest winner of the US Open since 1923 - by eight shots and with a record score by four.
His rise to the top has seen him finish in the top five in ten of his last 11 official events and he becomes the fourth European World Number One in the last 12 months after Westwood, Martin Kaymer and - for the last nine months - Luke Donald.
McIlroy said: "It was tough today, especially seeing Tiger make a charge. I knew par golf would probably be good enough and that's what I was trying to do, so to shoot one under is very nice and I was able to get the job done.
"My short game all week has been very good and it's what you need on a tough course like this. You know you are not going to hit every green."
The coronation could have happened a week ago, but McIlroy lost the final of the WGC - Accenture Match Play in Arizona.
Nobody can deny the Holywood golfer's right to be there. Since the US PGA Championship last August he has played in 11 ranking events and finished outside the top five in only one of them.
That was the Dubai World Championship presented by DP World in December where he came 11th while suffering from suspected Dengue fever and during that run there was also his victory in the non-ranking Shanghai Masters.
Woods, who had two eagles and four birdies in a flawless display that buried memories of his poor finishes in Abu Dhabi and at Pebble Beach earlier this season, said: "I've been hitting it like this, that's the thing.
"I hit it really good in the wind in Australia [in November] and thought there was no reason I couldn't do it again - and putt like I did the last two days. It came together.
"I figured I needed birdie-birdie [from the last two holes] to have a chance."
But, with McIlroy holding his nerve, birdie-eagle did not even prove to be enough.
His putting came to his rescue on the final day in West Palm Beach. On the front nine he saved pars from 13, eight and 12 feet and all day he did not miss once from under ten feet.
McIlroy now heads to the WGC - Cadillac Championship in Miami leading the European top four at the top of the Official World Golf Ranking.
