Nick Kyrgios

Kyrgios is a polarising figure in Australian sport - his superb tennis skills are often marred by poor behaviour on court, but the 22-year-old is now ready to take a more mature approach to his career.

No one is more aware of his own flaws than Kyrgios, which has made his failure to address them all the more frustrating.

"I think last year there were periods where I was really good and really bad," he said. "But at the end of the day I just need to know it's a long year.

The world No 1 proved too strong for the Australian, who had won nine of his previous 11 matches, winning 6-2 6-1 to secure his second Beijing title after his first victory in 2005.

Nadal, a two-time Grand Slam champion this year, never appeared in danger of losing to Kyrgios despite the fiery Australian making an encouraging start to the encounter.

Nadal, 31, secured the opening set thanks to two breaks of serve before racing through the second set against an out of sorts Kyrgios who struggled to cope with the greater consistency from Nadal's racket.

A stellar line-up in China in both the men's and women's events made for a memorable Saturday of action with Nadal against Dimitrov and Zverev against Kyrgios headlining the men's tournament.

World No 1 Nadal was first to book his place in Sunday's showpiece but needed more than two hours to register his 60th win of a memorable season that has also seen him claim two Masters titles and two more Grand Slam crowns.

The Australian, ranked 20th in the world, suffered another early Grand Slam exit at the US Open last month and has endured numerous peaks and troughs throughout a tempestuous career in top-level tennis.

He says his desire to lead "a normal life" is in conflict with his hunger to win tour matches, but rejected comparisons with another disaffected Australian player, Bernard Tomic.

A haphazard build-up, brutal draw and niggling injuries have cast Kyrgios as a Roland Garros underdog after the 22-year-old had been rated a serious challenger following his blazing run on hard courts.

Once the bookmakers' tip as the chief threat to the big five's dominance after twice conquering defending Open champion Novak Djokovic and then stretching Roger Federer to the limit in the match of the year in Miami, Kyrgios's stocks have since plummeted.

The 21-year-old made the announcement via his Twitter account on Good Friday.

The news was not unexpected as it was reported earlier in the week that he was considering pulling out of the Masters Series event in Monte Carlo which begins on Sunday.

Although Kyrgios did not give a reason for his withdrawal, it is believed he is suffering from fatigue following a busy start to the season.

Last week he was part of an Australia team which beat the United States to reach the semi-finals of the Davis Cup.

Kyrgios says he believes he has food poisoning.

The controversial 21-year-old added on social media that he needs to be at his best to play Federer, and didn't take the decision lightly.

"At this stage we think it's food poisoning, and I'm praying it's nothing more," he said.

"After a restless night of being sick I have nothing left and to play a great champion like Roger, I need to be at my best to have a chance.

"These are the matches we train for but I'm in no fit state to take to the court.

Kyrgios has beaten the world number two in a stunning straight-sets win at the Mexican Open in Acapulco, thanks to an unplayable service game including 25 aces.

Ace after ace after ace came in the first set as Kyrgios left Djokovic chasing shadows from behind the baseline, edging the Serb in a tie-break.

Kyrgios's stats v Djokovic:

Federer, who has claimed four Australian Open titles himself, believes Kyrgios isn't experienced enough to go the full length.

"To win, he drops, in my humble opinion,'' Federer told Fairfax Media. 

''To do anything, yes, first week no problem, but to go all the way it's a long way, and he's never been into a semis before, so first he has to prove to the world and himself that he can make the semis.

"So for me to start talking about him winning the tournament, Lleyton [Hewitt] never did it, and he was two times world No.1 at the end of the year.

The 21-year-old will end 2016 at a career-high ranking of 13th, but the past year has been far from plain sailing.

Kyrgios won his first ATP 500 title at the Japan Open in October, but was given a three-week tournament ban barely a week later after giving up in Shanghai against Mischa Zverev.

The incident was not the first time Kyrgios has been accused of 'tanking' and Philippousis has become the latest onlooker to demand increased focus from his compatriot.