SAN FRANCISCO -- There are two ways Luke Donald could be unseated as world No. 1 this week at the U.S. Open.
Rory McIlroy, who currently stands No. 2, would need to successfully defend the title he won a year ago at Congressional Country Club to have a chance. In that case, Donald would need to finish solo third or better to retain No. 1.
And third-ranked Lee Westwood would need to win what would be his first major championship to potentially knock Donald off the top of the Official World Golf Ranking. If Westwood does, Donald needs to finish 58th or better to stay No. 1.