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McIlroy opened his season on the European Tour with a chance to win his first event, the Abu Dhabi HSBC Golf Championship. But Martin Kaymer pulled away on Sunday to win by eight as McIlroy finished second.
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McIlroy's second event of 2011 was the Dubai Desert Classic, which he won in 2009 for his first professional victory. He was in contention through two rounds in this year's event before shooting 75-74 on the weekend to finish 10th.
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McIlroy was paired with fellow rising star Rickie Fowler for the first two rounds at the season's first major, the Masters.
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McIlroy was on the leaderboard from the start. He fired a 3-under 69 in the second round for a two-shot lead.
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McIlroy narrowly missed a birdie putt on 18 on Saturday, but still took a four-shot lead into the final round.
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Trying to become the second youngest player to win the Masters, McIlroy's four-shot lead at the start of the day quickly vanished, but he still went into the back nine tied for the lead. Then McIlroy tripled No. 10 (pictured), four-putted for double bogey on No. 12, and when his tee shot found Rae's Creek on 13, his hopes for a green jacket were over.
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In his first PGA Tour event since the meltdown at the Masters, McIlroy teed off as the defending champion at Quail Hollow. But he shot 75-72 and missed the cut.
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McIlroy opened his U.S. Open at Congressional with six birdies and no bogeys on Thursday and immediately jumped to the top of the leaderboard.
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McIlroy fired a 5-under 66 for a 36-hole total of 11 under — the lowest 36-hole score in the 111-year history of the U.S. Open. The rout was on.
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As his lead grew, McIlroy became a fan favorite at Congressional.
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Carlos M. Saavedra/SI
McIlroy's final putt gave him the U.S. Open by eight strokes and his first career major title.
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Many writers felt McIlroy's resounding victory signaled the start of a new era in professional golf.
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Shortly after his U.S. Open victory, McIlroy sat in the Royal Box at Wimbledon to watch the women's quarterfinal matches.
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Kieran Doherty / Reuters
After taking a month off following the U.S. Open, McIlroy failed to contend at the British Open at Royal St. George's. He finished tied for 25th.
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Paul Childs/Action Images/ZUMAPRESS.com
In the opening round at the PGA Championship, McIlroy ran into trouble on the third hole when he hit a tree root on his second shot.
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Fred Vuich / SI
McIlroy taped the wrist and gutted it out for the final three rounds at the PGA. He finished at 11 over par, well out of contention.
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McIlroy stepped out with tennis star girlfriend Caroline Wozniacki later in the summer. Here he celebrates with the Yale football team after Wozniacki's semifinal win at the 2011 New Haven Open.
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Ross Kinnaird/Getty Images
McIlroy went 66-65 on the weekend to finish in second place at the Alfred Dunhill Links in October. It was his fifth top-3 finish on the European Tour in 2011 and third in a row.
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In October, McIlroy announced a split with agent, Andrew "Chubby" Chandler.
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Alexander F. Yuan/AP
Rory McIlroy beat Anthony Kim (background) in sudden death at the Shanghai Masters for his first victory since the U.S. Open. McIlroy made a two-footer after Kim missed a three-foot par putt to seal the win.
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Tyrone Siu / Reuters
At the Hong Kong Open in December, Rory holed out from a greenside bunker for birdie on the final hole to win by one shot.