Rory McIlroy leads the Memorial Tournament by three shots after opening round . The Northern ##er shot an nine - under par 63 in Ohio City . The world No . 6 broke off his engagement to tennis star Caroline Wozniacki last week . Wozniacki was knocked out of the US Open in the first round earlier this week .
Rory McIlroy leads the Memorial Tournament by three shots after opening round . The Northern Irishman carded an nine-under par 63 in Ohio Thursday . The world No . 6 broke off his engagement to tennis star Caroline Wozniacki last week . Wozniacki was knocked out of the French Open in the first round earlier this week .