McIlroy did not play last week but adjustments stemming from past tournaments move him back into the top spot.
McIlroy's ranking average improves 0.063 points to 9.594 while Donald's slips 0.137 to 9.477. That gives McIlroy his third week overall at No. 1. Donald has been on top for 44 weeks.
The only other change in the Top 10 came as Martin Kaymer (5.581) edges past Steve Stricker (5.535) and into sixth. Stricker is seventh.
Louis Oosthuizen, who lost a playoff to Watson at the Masters, traveled nearly 10,000 miles for the Maybank Malaysian Open and came away a winner. He's up seven spots this week to No. 19. He was 27th before the Masters.
Pettersson improves his ranking to 68th from 110th.
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