BRISBANE BOUND: Rafael Nadal has confirmed he will play in this year's Brisbane International tournament.
BRISBANE BOUND: Rafael Nadal has confirmed he will play in this year's Brisbane International tournament. John Minchillo

Nadal's coming back to Brisbane

RAFAEL Nadal, who regains the world No.1 ranking on Monday, is on his way back to Brisbane.

Nadal has agreed to play his second Brisbane International from December 31-January 7.

Despite his quarter-final loss to Aussie Nick Kyrgios in Cincinnati on Friday, the 10-time French Open champion will become No.1 for the first time since 2014 when the official rankings are revised on Monday.

Brisbane tournament officials were confident Nadal wanted to start 2018 in Brisbane because of his enjoyment of his first visit.

Nadal appreciated that all three of his matches at Pat Rafter Arena were 5500-plus sellouts.

The 31-year-old Spaniard was ranked No.9 when he made the Brisbane quarter-finals after a 2016 season ruined by a wrist injury.

On his first day in Brisbane, Nadal made the prescient comment that he was "healthy, if I am to play a full season, I believe anything can happen''.

Brisbane tournament director Geoff Quinlan said Nadal's manager had confirmed the Spaniard's appearance.

"Rafa's manager Carlos Costa was in communication with me on Thursday and said Rafa is thrilled to be coming back," Quinlan said.

"We've been talking to his team for quite a while and we're delighted to have him confirmed.

"He was such a huge success in Brisbane in 2017. We had four record sessions for attendances, including the men's final because people were anticipating he'd be in the final.

"The reaction of the crowd was as rapturous as it was because they'd never seen Rafa play previously. He was a huge presence at the tournament, making time for fans and having an open training session.''

Nadal has won four titles this year and last week said his return to the top ranking, which he first held in 2008, was "something special".

"A lot of things have happened since the last time I was in this spot. Injuries and some tough moments,'' he said in Cincinnati.

"But I have held the passion and the love for the game - and that's why I have the chance to be back in that position again.''

Third-ranked Roger Federer will contest the No.1 ranking with Nadal and Andy Murray through the course of the season, with Murray (hip) and Federer (back) expected to be fit again to play at the US Open next week.

The pregnant Serena Williams has set all 2018 week one tournaments on alert by again outlining her desire to defend her Australian Open title in January.

Williams is due to give birth next month and had been hitting tennis balls as recently as last month.

The 35-year-old admitted in an interview last week her time frame to return to the tour in Australia was "outrageous".