Navratilova: Serena is favorite for Australian Open

The emotional pressure has been growing for Serena Williams as she seeks a record-equalling 24th Grand Slam singles title. She knows, at the age of 38, that time is running out for her to tie and then beat that record. And she has lost her last four major finals.

That's why I think Williams winning a tournament in Auckland last weekend - for her first title in three years, as well as her first since becoming a mother - was such an important moment. Taking that title would have been an emotional release that should help her at the Australian Open, and it's why she's the favorite at Melbourne Park.

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That title should rub out some of the doubt that has been building in her mind about whether she could perform in finals. When you get to several finals, and then don't perform in those matches, that scar tissue starts to build up in your mind. Just landing the Auckland title, even though she didn't beat anyone at the truly elite level, will help Williams to feel like a winner again.

Nothing takes the stress away from a tennis player like playing and winning matches. You can be sure that Williams will be feeling better about herself now that she had been before any other major over the last couple of years. And if she reaches the final of the Australian Open, that experience in Auckland, of taking the final step, will be even more valuable to her. While I would still like Williams to play a little bit more - she has had just five matches since last September's US Open final, all of them in Auckland last week - she's healthy, she's fit, and she's as motivated as she's ever been.

It looks to me as though Ashleigh Barty should be able to handle the pressure of playing at her home Grand Slam as the WTA World No.1. People are going to be looking at the WTA Rankings and saying that it means that Barty should win the tournament. I am not sure what Ash is feeling but I think that's going to be a tricky proposition for her. Not necessarily because of the expectations from the Australian public, but because of the faster surface at Melbourne Park. Her game is better suited to slower surfaces - such as the French Open clay, where she won her first major last year - and I think she is more vulnerable on the fast hard courts in Melbourne.

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She's yet to reach a semifinal at the Australian Open. We'll see if she changes her strategy and becomes a bit more aggressive, maybe going bigger earlier in the rally and getting to the net a bit more on this faster surface.

Coming just days into the season, the Australian Open is always such a crapshoot. Everybody's rusty - it's just a question of which level of rustiness you're on, and whether you're less rusty than everyone else. But these faster courts tend to favor the big hitters. Just look at last year's final between Naomi Osaka and Petra Kvitova; those players are contenders again this year.

Though Osaka is the defending champion, she's also a bit of a wildcard. When her game is on, she can beat everybody, and when it's off, she can have some early losses. And you never know what you're going to get with her emotionally, but she obviously likes the court and the set-up, having won last year. You also can't discount Kvitova, who came so close to winning last year's title, while another big hitter Karolina Pliskova will be feeling good about herself after winning a title in Brisbane. Also keep an eye on Simona Halep - she isn't a big hitter but she showed with her victory at Wimbledon last year that she can win on faster surfaces.

It's Caroline Wozniacki's last tournament before she retires and there will be lots of support from the crowd for the 2018 champion. Aussies really love her and what’s not to love? But it's going to be a mixed bag of emotions for her and that might be the biggest challenge. How can she control that? It's going to be hard for Wozniacki not to get nostalgic while she's on court; she will have a hard time keeping her mind from wandering off the path of trying to win a match. I don't think Wozniacki's got any ideas of winning the tournament but, for sure, she would like to do well, at least get into the second week and go out on a high. Here's hoping that happens!