Serena Williams says she wants to “move on to bigger and better things” following her first match back since her controversial US Open final defeat by Naomi Osaka.

Williams, 37, was beaten by her sister Venus 4-6 6-3 10-8 in an exhibition match in Abu Dhabi on Thursday.

The 23-time Grand Slam champion subsequently refused to discuss her confrontation with umpire Carlos Ramos in September’s final in New York.

“I don’t avoid anything,” she said.

“I just don’t have time to talk about that.

“I talked about it, everyone talked about it for months and months and months and it’s best to move on to bigger and better things.”

Williams got a code violation for coaching, a penalty point for racquet abuse and a game penalty for calling the umpire a “thief” in during the loss to Osaka.

She later accused him of sexism and was fined $17,000 (£13,450) for the code violations.

Speaking at the Mubadala World Tennis Championship, Williams said equalling Margaret Court’s record of 24 Grand Slam titles was a “significant” goal for 2019.

Williams’ first chance to tie the record will be at the Australian Open from 14-27 January.

“It has always been significant since I got 22, then 23,” she said.

“It’s something that I clearly want but I have to be able to get there and beat a lot of good players to get it.”

She added that she felt “pretty fit” in her defeat by Venus.

“I was running and running and never got tired except for one point but then I got over it in 20 seconds, so I think that was really the highlight for me,” she added.

Before the match, Williams praised the introduction of more ranking protection for new mothers on the WTA Tour.

German great Boris Becker says he is not going to be women’s world number one Simona Halep’s new coach.

Romanian media reported Halep, who split up with long-time coach Darren Cahill in November, would start working with the six-time Grand Slam winner.

Becker said although he admired Halep, who won her first Grand Slam at this year’s French Open, he was busy with his other tennis commitments.

“It was never discussed,” the 51-year-old tweeted on Thursday.

Becker coached men’s world number one Novak Djokovic between 2014 and 2016, helping the Serb win six Grand Slam titles.

Becker is currently the head of German men’s tennis and also works as a television analyst for several companies, including BBC Sport.

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Serena Williams has praised the introduction of more ranking protection for new mothers on the WTA Tour.

Players coming back from childbirth or injury can use their previous ranking to enter 12 tournaments over a three-year period.

In addition, they will not face a seeded player in an opening round.

“I think it’s great,” said Williams who gave birth to daughter Alexis Olympia in September 2017 and returned to action in February 2018.

“Women that are younger can go out there and have kids and not have to worry about it, and not have to wait until the twilight of their years to have children, and I think it’s a really great rule.”

• WTA changes rules on returning mothers
• Most players not in favour of changing seeding rules

Williams, 37, was not seeded at the French Open, her first Grand Slam appearance following her return, but was given a seeding of 25 for Wimbledon, despite being outside the top 32 in the rankings. She is now ranked 16th and will be seeded for next month’s Australian Open.

The WTA’s rule change comes after the organisation canvassed the opinions of players earlier in the year.

World number one Simona Halep and five-time Grand Slam champion Maria Sharapova had both offered their support to Williams, but others like Petra Kvitova, Victoria Azarenka and Johanna Konta expressed reservations.

Williams added: “I think having gone through the experience myself really opened my eyes. Would have I done it sooner had there been different rule changes? I don’t know. But now there is an opportunity, people don’t have to ask that question.”

The 23-time Grand Slam champion will be in action against sister Venus in Abu Dhabi on Thursday in her first match since September’s US Open final defeat by Japan’s Naomi Osaka. That match was overshadowed by her outburst at chair umpire Carlos Ramos, whom she called a “liar” and “thief”.

She was docked a game for verbal abuse following a point penalty for racquet smashing and a code violation for coaching. She was subsequently fined for her outbursts.