Jordan Spieth didn't chase down Jason Day at the PGA Championship, but he did catch Rory McIlroy.
Spieth is the fifth American to ever reach No. 1 - joining Fred Couples, Tom Lehman, David Duval and Tiger Woods. At 22, he is the second-youngest player to ever reach the top spot, behind only Woods, who did it at 21.
As for Sunday's champion, Day is now the third-ranked player in the world, his highest ranking to date.
Others making upward moves in the top 10 include Justin Rose, now fifth, and Dustin Johnson, now seventh.
And in our weekly Tiger Woods watch, the former world No. 1 dropped from 278th to 286th with his early exit in Wisconsin. He sits sandwiched between Brazil's Lucas Lee and South Korea's S.J. Park.
Here is your new top 10, with a new No. 1, for the week of Aug. 16: 1. Jordan Spieth, 2. Rory McIlroy, 3. Jason Day, 4. Bubba Watson, 5. Justin Rose, 6. Jim Furyk, 7. Dustin Johnson, 8. Rickie Fowler, 9. Henrik Stenson, 10. Sergio Garcia.