Cape Town - The return of 13-time Grand Slam winner Novak Djokovic to the US Open poses a serious threat to defending champion Rafael Nadal and Australian Open winner Roger Federer.

On the women's side, 23-time Grand Slam champion Serena Williams could snatch her 24th Grand Slam crown with a home crowd behind her.

The most dangerous player right now is definitely Djokovic. He won his first Grand Slam since recovering from an elbow injury by beating South Africa's No 1 Kevin Anderson - ranked No 5 by the Association of Tennis Professionals (ATP) - at the Wimbledon championships.

After defeating Federer at the Cincinnati Masters last week, he became the first player to win all nine Masters 1000 titles, something not even his two great rivals have been able to achieve.

Tennis analyst Bruce Davidson believes he is the player to watch.

"Novak is definitely in with a chance," he said. "He is back to his top game and, for the past few months, sent out a warning that he would be a strong contender for the No 1 ranking again."

The Serbian first reached the summit of the ATP rankings in 2011.

"His good form on grass proved that and his win last week in Cincinnati sent a strong warning to his opponents. He may not go into the US Open as one of the top four seeds, (but he) is definitely a favourite for the New York title," said Davidson.

The sixth seeded player may face Federer in the quarter-finals if he gets there.

Top seed Nadal will open his account against compatriot David Ferrer in a rematch of the 2013 French Open final. Nadal, currently the world No 1, has managed to win five titles this year: the Monte Carlo Masters, the Barcelona Open, the Rome Masters, the French Open and the Rogers Cup. The latter was his only hard-court title.

Swiss star Federer will be looking to win his first US Open since 2008 and to extend his record of 20 Grand Slam titles. Other than his record Australian Open victory, he won the Rotterdam Open and the Stuttgart Cup.

He skipped the clay season as chances of beating Nadal on red clay were almost nonexistent. The Stuttgart Cup was his 98th career title. He will begin his journey against Japan's Yoshihito Nishioka on Monday and could face 30th seed Australian Nick Kyrgios in the third round.

READ: SA's Lloyd Harris qualifies for US Open

South Africa's hopes will be pinned on Anderson. Davidson believes his results since reaching the final at Flushing Meadows last year prove he can cause an upset.

"His ranking has shot up impressively and he enjoys the US hard courts. He will go into this year's US Open with added confidence, having reached the final at Wimbledon," said Davidson.

"I believe Kevin is capable of winning a Grand Slam and he has been very close. The question is when he will do it. He is definitely playing well enough to do it this year."

The Johannesburg-born player lost 6-3, 6-3, 6-4 in last year's final to Nadal. He faces unseeded American Ryan Harrison in his opener on Monday.

A South African joining Anderson is rising star Lloyd Harris. In arguably the biggest match of his career, he beat Juan Cruz "JC" Aragone of the US 6-4, 6-2 on Friday to qualify for the main draw.

READ: Lloyd Harris' US Open qualification worth R770 000 - at the least!

Williams has not won a Grand Slam title since giving birth to daughter Alexis Olympia in September, despite coming close to winning Wimbledon. She lost to German Angelique Kerber in the final.

Coming to this event, she will be aiming to equal the 24 Grand Slam record set by Australian Margaret Court.

"She is capable of winning the US Open. She has won the tournament a few times," said Davidson.

"She loves the city and atmosphere and playing in front of her American home crowd. I believe that, if she is fit enough, she can go all the way."

With Romanian Simona Halep having finally won a Grand Slam title, Davidson believes there is more coming from her, but it's difficult to call the winner.

The last Grand Slam tournament of the year starts on Monday.