How players fared in their debut at No. 1 in the world:
Dustin Johnson — Won the WGC-Mexico Championship in 2017.
Jason Day — Tied for 10th at the Tour Championship in 2015.
Jordan Spieth — Missed the cut at The Barclays in 2015.
Adam Scott — Won the Crowne Plaza Invitational at Colonial in 2014.
Rory McIlroy — Tied for third at the WGC-Cadillac Championship in 2012.
Luke Donald — Tied for seventh at the Memorial in 2012.
Martin Kaymer — Tied for 24th in the WGC-Cadillac Championship in 2011.
Lee Westwood — Runner-up at the WGC-HSBC Champions in 2010.
Vijay Singh — Won the Canadian Open in 2004.
David Duval — Won the BellSouth Classic in 1999.
Ernie Els — Runner-up at the Scottish Open in 1997.
Tiger Woods — Tied for 43rd at the Buick Classic in 1997.
Tom Lehman — Was No. 1 for only one week and did not play.
Nick Price — Tied for 10th at the World Series of Golf in 1994.
Fred Couples — Tied for 13th at the Players Championship in 1992.
Ian Woosnam — Won the Masters in 1991.
Nick Faldo — Tied for fourth in the European Open in 1990.
Greg Norman — Won the World Match Play Championship in 1986.
Seve Ballesteros — Tied for fourth at the Italian Open in 1986.
Bernhard Langer — Tied for 16th at the Masters in 1986.