Phil Mickelson has failed in his first 20 attempts to win the U.S. Open.

If he’s to end the streak at Congressional Country Club in Bethesda, Md., this weekend, the most difficult part may be staying motivated without Tiger Woods in the field.

“I’ve always felt as though Tiger helped bring out some of my best golf over the years,” Mickelson said Wednesday. “The challenge now, without him competing this week, is pushing myself to achieve a level of play that is in there without him forcing me to do so. In that sense, it might be a little bit more difficult.”

Woods will miss the tournament for the first time since 1994 as he recovers from knee and ankle injuries.

Mickelson, who turns 41 today, finished second at the U.S. Open in 1999, 2002, 2004, 2006 and 2009. Each loss came in its own dramatic way.

He fell to Payne Stewart on the final hole at Pinehurst in 1999 as Amy Mickelson was set to give birth to the couple’s first child.

Three years later, Mickelson lost to Woods at Bethpage as boisterous New York crowds tried to cheer him to victory.

In 2004, two months after capturing his first major title at the Masters, Mickelson lost to Retief Goosen following a bogey on the 17th hole at Shinnecock Hills.

Mickelson’s most noteworthy collapse came in 2006 at Winged Foot, where he held a two-shot lead with three holes to play. A bogey on the 16th hole and a double-bogey on the 18th allowed Australian Geoff Ogilvy to take the title.Two years ago, again at Bethpage, Mickelson played in the tournament while his wife was battling breast cancer. He held a share of the lead with five holes to play until making bogeys on the 15th and 17th holes. Lucas Glover went on to win. Englishmen Luke Donald and Lee Westwood are co-favorites for the tournament, listed at 10-1 odds, according to the Las Vegas Hilton’s Race and Sports Book. Mickelson is next at 12-1. Mickelson has said the U.S. Open is the major he wants to win the most. “Deep down I have the belief that I can come out on top,” he said.