The 29-year-old top seed won 7-6 (7/1), 6-2, 4-6, 6-4 to lift the penultimate major trophy of a season in which he has earnt more than $3m by producing some of the best tennis of his career.

Agassi, enjoying a late revival after slumping down the rankings, was cheered on by new girlfriend Steffi Graf.

It was the American's 10th major title, tying him with Pete Sampras, and the 44th win of his career.

Not only that, the win means Agassi becomes the first person to take both the Roland Garros and the Paris Open titles in the same year.

But it was nothing less than was deserved by Agassi - who heads the year-end world rankings for the first time in his career having slid out to 141st two years ago.

The 29-year-old Las Vegan's French Open triumph in June made him the first man to win all four Grand Slams on different surfaces.

On this occasion Agassi was not at his most brilliant - dropping a set in the third round against Dutchman Sjeng Schalken and in Saturday's semi-final battle against Nicolas Lapentti of Ecuador.

He certainly benefited from the early departure through injury of both Sampras and defending champion Greg Rusedski.

And though Safin served up 19 aces to Agassi's seven, the opening rounds - in which he battled his way through five tiebreaks - took their toll on the young pretender.

This was only the Russian's second ATP final since beating Rusedski in Boston last August.

He sank without trace in the first-set tiebreak having pushed Agassi all the way over the opening 12 games.

Agassi now joins Yevgeny Kafelnikov, Gustavo Kuerten and Pete Sampras at the season-ending ATP Tour World Championships in Hanover starting on November 23.

Nicolas Kiefer of Germany, American Todd Martin, Sweden's Thomas Enqvist and Nicolas Lapentti of Ecuador are also expected in Germany.

Andre Agassi factfile:
World Ranking: 1
Highest ranking: 1 (First time on April 10, 1995)
Age: 29 (April 29, 1970)
Residence: Las Vegas, Nevada
Coach: Brad Gilbert
Career prize money: $18,189,614
Career titles: 44
Grand Slams: Wimbledon 1992; US Open 1994, 1999; Australian Open 1995; French Open 1999