Serena Williams is probably the first 28th-seeded favorite in Grand Slam history. Her ranking is not up to expectations due to illness and injury over the last year, but she is back now and in great form.
Williams was unable to play in New York last year because of a foot injury. Her last moment at the US Open was the dubious situation that involved her losing a match to Kim Clijsters after a foot-fault call caused her to lose her temper.
The all-time great is just a handful of sets away from capturing her 14th Grand Slam title. Here are five reasons she is guaranteed to win the 2011 US Open.
This tournament really is Serena's to lose. Of all the quarter-finalists, she is the only one that has won a Grand Slam tournament.
Experience normally plays a big part at the business end of Grand Slam tournaments. There are a few other players in the draw who have made a Grand Slam final, but no one can come close to the experience of Williams on the big stage.
It's also rare for Williams to lose a Grand Slam match to a player who does not have a championship pedigree. If she is going to lose this tournament, someone is going to have to come up with the best match of her life.
There was a time this year when Williams was unsure if she would even be able to play on the WTA Tour again. She is thankful to be back playing and knows how lucky she is just to be out there.
Her missed time combined with the condition that forced her older sister Venus to retire from her second-round match will drive the normally determined Williams even more. She is one of the most mentally strong athletes in sports.
Williams also wants to re-assert her dominance in women's tennis. After winning Wimbledon in 2010, she was primed to become the best player of all time and will look to get back on that path by winning the US Open.
Williams won the Olympus US Open Series and has not lost a match since Wimbledon. She's on top of her game right now, a scary proposition for anyone who is standing on the other side of the net.
In the third round of the Open, No. 4 seed Victoria Azarenka played the best set of tennis in her life in the second set. The result? Williams won the set in a tiebreak to advance to the fourth round.
It's clear that when Williams is healthy she is simply the best in the game, especially on a hard court. In her recent comeback she has been playing more consistent than in the past, making it even harder to stay with her.
Cljsters had won the last three Grand Slams played on a hard court prior to this event. An abdominal injury caused her to not be able to play this year's US Open, however.
Clijsters may be the only player in today's game who can defeat Williams if Serena is at her best. She did just that in the 2009 US Open semifinals.
Williams won the US Open in 2008 and didn't play in 2010, so that means Clijsters is the only player to defeat her in New York in the last three years.
Williams has the best overall serve in women's tennis, and it's usually an overwhelming advantage against her opponents.
Most women on the WTA Tour struggle mightly to hold their serves on a consistent basis. Of all the players left in the draw aside from Serena, only Sam Stosur possesses a strong serve.
This factor alone puts a lot of pressure on Serena's opponents. They know that it takes a big effort to break her, so their serving games become that much more important.