While all eyes are on Roger Federer and Serena Williams, who begin the defence of their US Open titles at Flushing Meadows on Monday, here are some lower-ranked players who could make an impact at the last Grand Slam of the year.

Robin Soderling (Sweden)

World ranking: 12

Gifted with a thunderous forehand, Soderling has the ability to leave many opponents huffing and puffing as they chase after his winners. He also employs a high-risk strategy of blunting his opponents' strengths instead of exploiting their weaknesses.

Except for Roger Federer, no one has managed to blunt his tactics at the last two Grand Slams and with a reasonable draw, the French Open runner-up could be an outside bet for the US Open title.

Marin Cilic (Croatia)

World ranking: 17

'Baby Goran' has won three hardcourt titles in his career, including two this year but has struggled to reproduce the form on the big stage.

With his long limbs and powerful double-handed backhands, he has the ability to blow away opponents but his mental strength has so far failed to match up to his obvious talent. Should he manage to get his act together, he could join fellow Croatian Goran Ivanisevic in the Grand Slam winners' club.

Marat Safin (Russia)

World ranking: 58

Whether winning a title in grand style or filling the players' box with his bevy of "blondies" Safin has been headline news for a decade. From next year the sport will have to do without his brooding brilliance because he will be hanging up his rackets for good at the end of the season.

Nine first-round losses in 2009 suggests that his farewell appearance in New York may only be a fleeting one but since the only thing to expect from Safin is the unexpected - the 2000 US Open champion could surprise everyone with a last run towards glory.

Kim Clijsters (Belgium)

Will arrive in Flushing Meadows without a ranking but the 2005 champion will be the one player most of the women who make up the 128-strong draw will want to avoid. In the seven matches she has played since returning to the tour following a 2-1/2 year hiatus, she has already claimed the scalps of four top 20 players, including French Open champion Svetlana Kuznetsova.

The gritty baseliner has lost none of her mental toughness and showed she can still cause damage with her solid groundstrokes. After such an impressive comeback, Lindsay Davenport has tipped her to become the first mother to win a Grand Slam title since Evonne Goolagong triumphed at Wimbledon in 1980.

Victoria Azarenka (Belarus)

World ranking: 8

Started off the year with a bang by grabbing two titles in quick succession and her win over Serena Williams in the Miami final showed she has the ability to produce the goods at the big events.

One of the sport's loudest grunters, she will be hoping to cause a racket with her stinging double-handed backhands rather than her ear-splitting shrieks.

Caroline Wozniacki (Denmark)

World ranking: 9

Hailing from a family of professional athletes, it was inevitable that the Dane would succeed at her chosen sport. In a big year for the 19-year-old, she has produced consistently good results to break into the top-10 for the first time.

Has an exciting game with a sizzling double-handed backhand and also has the ability to outwit her opponents by varying the height and speed of the ball. Reached the last 16 in New York last year and is now primed to go deeper in the draw.