It is the fourth change at the top between the two since March. A fifth could happen as soon as this week, as Rory McIlroy will play the Wells Fargo Championship while Donald is idle.
Lee Westwood, Bubba Watson and Hunter Mahan round out the top 5. Steve Stricker and Tiger Woods come next, each moving up a spot as Martin Kaymer drops to eighth. Justin Rose and Phil Mickelson swapped ninth and 10th, respectively.
Playoff runner-up Ernie Els should now be safe for the U.S. Open, climbing 23 spots to 40th. The top 60 players in the ranking two weeks before the event are exempt into the field at Olympic Club.
Bernd Wiesberger moved up to 95th, a gain of 75 places, after taking his maiden European Tour title at the Ballantine's Championship in South Korea.