Serena Williams’ decision on whether or not to defend her Australian Open title four months after giving birth to her first child was never about merely being able to play at Melbourne Park.

The seven-time Australian Open champion confirmed Friday she wouldn’t attempt to defend the title she won here last year, saying she wasn’t completely sure she could win it.

Williams played in an exhibition tournament last weekend in Abu Dhabi and indicated after her loss to French Open champion Jelena Ostapenko that she might not travel to Melbourne.

“After competing in Abu Dhabi I realized that although I am super close, I’m not where I personally want to be,” Williams said in a statement Friday. “My coach and team always said ‘Only go to tournaments when you are prepared to go all the way.’ I can compete - but I don’t want to just compete, I want to do far better than that and to do so, I will need a little more time.

“With that being said, and even though I am disappointed about it, I’ve decided not to compete in the Australian Open this year.”

Williams was pregnant when she won at Melbourne Park last year, her Open-era record 23rd Grand Slam singles title. She gave birth to her daughter, Alexis Olympia, in September.

The 36-year-old Williams needs only one more major title to equal the all-time record held by Margaret Court, who won 13 of her 24 Grand Slam titles before the Open era began in 1968.

Her withdrawal comes less than 24 hours after fellow former world No. 1 Andy Murray withdrew from the men’s event with a chronic hip injury.

Other star players, including top-ranked Rafael Nadal, six-time champion Novak Djokovic and 2014 winner Stan Wawrinka, also are dealing with injuries.

Williams last year beat older sister Venus in the final. In terms of total years, it was the oldest Grand Slam women’s final in the Open era —Williams sisters combining for 71 years, 11 months.

Venus has returned and is playing in Sydney next week to prepare for the Australian Open, which begins Jan. 15.

Serena will sit one out, but is promising to return in future.

“The memory of last year’s Open is one that I will carry with me, and Olympia and I look forward to coming back again,” she said. “I appreciate the support and understanding of my fans and everyone at the Australian Open.”

Tournament director Craig Tiley said Serena Williams waited as long as she could before letting organizers know she wouldn’t be able to compete.

“I’ve been in constant contact with Serena and her team and know this is why she has pushed it and pushed it until the 11th hour to make her final decision,” he said. Organizers later announced that French Open semifinalist Timea Bacsinszky had also withdrawn after failing to recover in time following surgery on her right hand in September.

With Serena Williams out, the women’s singles title at Melbourne appears to be wide open. No. 1-ranked Simona Halep and No. 3 Caroline Wozniacki are bidding to win their first Grand Slam singles titles.

Also in the mix will be No. 2-ranked Garbine Muguruza, last year’s Wimbledon winner, U.S. Open champion Sloane Stevens and Venus Williams, who will be aiming to win her eighth major singles title at the age of 37.

Murray’s hip still an issue

Andy Murray needed only a couple of days in Australia to realize the hip problem that has kept him out of competitive tennis since Wimbledon was not going to improve in time for the season's first major.

The five-time finalist withdrew from the Australian Open on Thursday, two days after pulling out of a tuneup event in Brisbane before his first match.

Confirmation of his absence came hours after Kei Nishikori announced that he, also, wouldn't have enough time to fully recover from a torn wrist tendon before the Australian Open starts Jan. 15 in Melbourne.

Murray was preparing to leave Australia at the same time as injured former champions Novak Djokovic and Rafael Nadal were on the way to Melbourne.

"Sadly I won't be playing in Melbourne this year, as I am not yet ready to compete," Murray said in a statement. "I'll be flying home shortly to assess all the options but I appreciate all the messages of support and I hope to be back playing soon."

Australian Open tournament director Craig Tiley said he understood Murray's early decision.

"We are fully aware that Andy has been going through a difficult period with his hip and that he's done everything possible to prepare for the Australian summer," Tiley said. "This is a very hard decision for Andy and we totally respect it."

Former No. 1-ranked Murray, a three-time major winner, has not played a competitive match since a quarterfinal exit at Wimbledon last July.

In a heartfelt social media post earlier in the week, the 30-year-old Murray contemplated surgery as an option after failing to overcome the pain with rest and rehabilitation.

In the lengthy Instagram post, Murray said he'd worked hard on the conservative option of rest and rehabilitation but was now having to consider alternatives.

"Obviously continuing rehab is one option .... Surgery is also an option but the chances of a successful outcome are not as high as I would like which has made this my secondary option and my hope has been to avoid that."

Murray spent 41 weeks at No. 1 in the rankings until last August, but slipped to a year-end No. 16 because of his prolonged absence from the tour.

"I would give anything to be back out there. I didn't realize until these last few months just how much I love this game," Murray posted "It's quite demoralizing when you get on the court it's not at the level you need it to be to compete at this level.

"Sorry for the long post but I wanted to keep everyone in the loop and get this off my chest as it's really hurting."

Djokovic, who has beaten Murray in finals four times as he collected his six Australian titles, posted a statement on his website saying he wasn't sure he'd be able to play at Melbourne Park.

A right elbow injury has kept him off the tour since July. He plans to play in two exhibition tournaments in Melbourne next week before deciding.

Top-ranked Nadal, who lost last year's Australian final to Roger Federer and went on to win the French and U.S. Open titles, has been struggling with a right knee problem and withdrew from the Brisbane International this week, delaying his return until an exhibition tournament next Wednesday.

There's also doubt over Serena Williams' title defense. Williams, who was pregnant when she won the Australian title — her record 23rd singles major in the Open era — and gave birth to her daughter in September, played an exhibition in Abu Dhabi last weekend and said she wasn't sure if she'd be able to play in Melbourne.

Williams said after her loss to French Open champion Jelena Ostapenko: "I don't know if I am totally ready to come back on the tour yet. I know that when I come back I definitely want to be competing for championships."

Tiley said he was in daily touch with Williams' management.

"I still believe she will be," in Australia, Tiley said. "She has made it very clear to me ... she'll do everything she possibly can to be here."