Jordan Spieth's missed cut at The Barclays means his first stint as world No 1 was one of the shortest in golfing history.
The 22-year-old was making his first start since moving above Rory McIlroy by being runner-up at the PGA Championship and would have retained top spot with a tied-14th finish or better at Plainfield, but suffered an early exit after an error-filled couple of rounds.
The missed cut was only Spieth's third in 22 starts over 2015, but sees him drop back to world No 2 below McIlroy after just a fortnight in pole position. Here are the other well-known names that had similarly short spells during their first time at the top of the rankings...
Fred Couples - March 1992 (one week)
A two-shot victory over Raymond Floyd at Augusta gave Couples his solitary major title and saw him become the first American to move to world No 1, although he found himself back in second spot a week later.
Despite neither Couples nor Nick Faldo featuring the following week, the Englishman had been pushed back to the top of the rankings by virtue of having a higher average, only for Couples to reclaim the position following a tied-59th finish at the event now called the Wyndham Championship.
Couples would stay ahead for 15 weeks until the Open Championship at Muirfield, where he missed the cut as Faldo moved above him again by claiming his second career Claret Jug.
Tom Lehman - April 1997 (one week)
Lehman closed the gap on Greg Norman when the Australian missed the cut at The Masters and moved above him with a strong week at the RBC Heritage, then known as the MCI Championship.
That would be Lehman's only week at the top of the pile in his career, as Norman returned to world No 1 by finishing runner-up at the Open de Espana just seven days later.
Of the 18 players to have ever topped the OWGR rankings, the former Open Champion is the only one to have spent just one week of his career in top spot.
Tiger Woods - June 1997 (one week)
The 14-time major champion may have been the man to beat for a combined 683 weeks during his career, but Woods' maiden spell at the top of the pile was over in just a week.
Having become the youngest player in history to reach world No 1, the then 21-year-old lost his top spot at the first attempt when he followed a fourth-place finish at the US Open with a tie for 43rd at the Buick Classic.
Ernie Els and Greg Norman would hold the position over the coming weeks, only for Woods to return to the position for a second time a month later by claiming the now defunct Motorola Western Open title.
Ernie Els - June 1997 (one week)
Golf had its second new world No 1 in as many weeks when the South African claimed two consecutive victories, but the 'Big Easy' slipped back down the rankings by the time he teed off for his next tournament.
A second major win at the US Open was followed by a triumph at the Buick Classic a week later, only for Norman to win the FedEx St Jude thus lifting the Australian back to top spot.
It wouldn't be the last time we'd see Els as the world's best, with the four-time major champion returning to the top of the OWGR standings for two separate four-week stints a year later.
Rory McIlroy - March 2012 (two weeks)
The Northern Irishman will hope his latest stint at the top of the world rankings is longer than his first spell as world No 1, which came by winning the Honda Classic.
McIlroy held on to top spot a week later by finishing higher than Luke Donald at the WGC-Cadillac Championship, but he had seen the Englishman reclaim the world No 1 ranking by the time he next returned to the course.
Donald's win at the Travelers Championship had parachuted him above McIlroy, with the pair interchanging between first and second on numerous occasions in the months that followed.
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