In 2005, DiMarco lost a sudden-death playoff with Tiger Woods to finish second in The Masters. The final round pairing of Woods and DiMarco featured a famous chip from Woods which took an incredibly long time to drop into the hole for a birdie on the par three 16th, and stretch his lead to two. The Masters result moved DiMarco into the top ten of the Official World Golf Rankings. DiMarco finished as the runner-up in a major for the third time at the 2006 Open Championship at Hoylake; Tiger Woods beating him by two strokes. DiMarco achieved his four-round score of 70-65-69-68 (272, −16) less than three weeks after the death of his mother.
Arguably, DiMarco enjoyed his most consistent success from 2002 to 2006, when he was ranked in the top ten of the world rankings for 61 weeks, going as high as number six in the world in 2005. DiMarco was also a member of the U.S. national team in the 2003 and 2005 Presidents Cup, and the Ryder Cup competitions in 2004 and 2006. DiMarco sank a 15-foot (4.6 m) putt to beat Stuart Appleby and clinch the 2005 Presidents Cup.