Story highlights

Chris Evert and Martina Navratilova assess new No. 1 Angelique Kerber

Pair say Kerber's mentality has played a big part in her success in 2016

Kerber, Radwańska, Halep and Kuznetsova also under spotlight

CNN  — 

Women’s tennis has a new world No. 1. But how did Angelique Kerber do it?

CNN’s Open Court show asked two legends of the game, 18-time grand slam winners Chris Evert and Martina Navratilova, to assess the German’s rise and run the rule over three other players in the top 10, Agnieszka Radwanska, Simona Halep and Svetlana Kuznetsova.

Kerber won her first two majors in 2016, at the Australian Open and US Open, and ended the year as world No. 1 despite losing the season-ending WTA Finals to Slovakia’s Dominika Cibulkova in Singapore.

Evert and Navratilova agree that a change in temperament has helped the 28-year-old Kerber usurp Serena Williams.

The pair – good friends who faced off 80 times during their playing days – chatted to Open Court during the WTA Finals.

Angelique Kerber

World ranking: 1
Titles won in 2016: 3
Slams won in 2016: 2
2016 prize money: $10,136,615

Chris Evert: “She’s come on really strong this year. It’s surprising winning two grand slams. Serena is still playing some high level tennis but I don’t remember the last time anyone besides Serena won two grand slams in a year.”

It was, on the women’s tour, Justine Henin in 2007.

Evert continued: “She’s just so aggressive, she has a little more sting on her serve, she’s finally that true lefty I had so much trouble with playing against Martina. She’s coming in and volleying and no-one has short, acute angles like Kerber. I love the mental side, she’s really gaining strength.”

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Martina Navratilova: “When Garbine Muguruza won the French Open I thought ‘OK, she’s going to be a force’ and I thought she had a better chance of finishing at No. 1. Angelique came, not out of nowhere, but I did not see her as a No. 1 at the end of the year.

“She’s really playing the best tennis, the most consistent, and she’s really believing in herself so much. She used to get upset with herself, and lose it for a couple of games or even lose a match but now she’s ready to go every point. Some players when they become No. 1 they put too much pressure on themselves but she thrives on it and is backing it up nicely.”

Angelique Kerber had a 2016 to remember, winning two slams and ending the year ranked No. 1

Agnieszka Radwanska

World ranking: 3
Titles won in 2016: 3
Slams won in 2016: 0
2016 prize money: $4,162,193

Evert: “I don’t really know if Radwanska can win a grand slam. I think everybody is cheering for her because she really is such a nice girl and she really deserves it. The big players – Serena and Svetlana Kuznetsova have a winning record against her – get her game.”

Navratilova: “She beats the players ranked below her but it’s really hard for her without a big weapon. Her big weapon is moving around the court really well and mixing it up but people get used to it. When you have a 120mph serve, like a Karolína Pliskova, or big ground strokes like Kuznetsova, she has a hard time being able to finish those matches against the big players.

“But you never know, things can work out for you – Marion Bartoli won Wimbledon (in 2013) without beating anyone in the top 10.”

 Poland's Agnieszka Radwanska, ranked third in the world, is yet to win a grand slam

Simona Halep

World ranking: 4
Titles won in 2016: 3
Slams won in 2016: 0
2016 prize money: $4,333,253

Navratilova: “She’s an amazing mover but I thought she was mentally tougher last year or the year before. She’s working with Darren Cahill, one of the best minds in the game, and she’s not taking advantage of it. She’s still fighting herself so much and gets down on herself.

“It’s one thing to be a perfectionist, you and I are that, maybe we should have been nicer to ourselves, but we didn’t let it get in the way of playing our best tennis. Simona gets so upset with one or two shots early in the match and then she loses it.”

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Evert: “That’s my one criticism of her – I want to shake her and say ‘Just be positive.’ If you remember Kerber used to be like that, she used to give little signs to her players’ box and get down on herself and she turned it around so there’s no reason Simona can’t.”

Navratilova: “There’s still time but you don’t want to be wasting time. The mentality, that’s something you should be able to control. Whether you are healthy or not, how fast you can run – they aren’t things you can work on, but the mentality should be.”

Evert: “She’s tweaked her game a little bit, she has a bigger first serve, it has a little bit more sting, she moves incredibly well but it’s the mental side. Hopefully she will do it, she’s a great player.”

Simona Halep has work to do on her temperament, according to Evert and Navratilova

Svetlana Kuznetsova

World ranking: 9
Titles won in 2016: 2
Slams won in 2016: 0
2016 Prize money: $2,396,479

Evert: “She’s had a great year. I remember watching her beat Serena this year in Miami. She looked great then and she’s kind of got that great all-round game – she doesn’t have any real weaknesses. She’s been her own worst enemy in the past but that mental side has improved.”

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Navratilova: “I don’t know what happened. I would like to talk to her. I thought she was going to retire – down in the 40s, 50s ranking going down. I thought she was going to fade away a couple of years ago then she comes back, gets another tattoo and starts beating everybody – amazing!”