After eight tour victories in three years - including last year's PGA Championship - and six of them in the last 14 months, Justin Thomas finally displaced Dustin Johnson last night as the world's number one player.
For a start Spieth, who is back up to No 3 in the rankings, is in action this week in his native Texas at the Byron Nelson Invitational desperate to put on a show for his home fans. It is the first time that a former Alabama golfer has moved into the No. 1 spot as the top golfer in the world.
Thomas has become the 21st world number one.
Thomas, 25 dethroned fellow American Dustin Johnson, who had led the rankings for 64 weeks since winning last year's Genesis Open in Los Angeles.
Thomas is the reigning PGA Championship victor, and Webb Simpson's victory Sunday gives the USA control of the four majors and The Players for the first time in 17 years.
He has pressed on this year with a win at the Honda Classic and three more top tens off the back off his punishing driving - despite his slight frame he averages 312 yards on the PGA Tour - and his uncannily accurate mid-range putting.
Webb Simpson won the Players Championship by four strokes.
The 2017 US PGA Championship victor said: "It's important, but it's not something where it's like I just want to do it once".
"It means a lot, but it's something I want to have for a long time, not something I just want to have once", Thomas said at the Players Championship where he tied for 11th.