SHENZHEN, China – Petra Kvitova had some big moments in 2015 – three Premier titles at Sydney, Madrid and New Haven, her first US Open quarterfinal and, for a brief period, getting back to No.2.

But there was something else that’ll go down in the record books – a shocking win over the World No.1.

“She went for broke on every serve, every return – I hit some second serves, 170, 175, and she would just hit them for winners,” Serena Williams said after falling to Kvitova in the Madrid semifinals.

“For sure I’m happy I won today,” Kvitova said after her 6-2, 6-3 victory in the Spanish capital.

“I had never beaten Serena before, so this is a really special moment for me, of course.”

With that victory, Kvitova became the only player to beat Williams in straight sets in 2015 – and with that, could the big-hitting Czech, a former World No.2, be the World No.1’s biggest threat in 2016?

She certainly knows how to bring her best on the biggest stages – also Williams’ favorite stages. Kvitova has two Grand Slam titles to her name, Wimbledon in 2011 and 2014, and she’s been to the semis or better at the Australian Open and French Open, and the quarterfinals of the US Open as well.

The World No.6 is also an impressive 17-6 in WTA finals – more importantly, 2-0 in Grand Slam finals.

“I don’t really like the beginning of the tournaments, for sure, but that’s how it is – it’s probably normal that I’m improving my game with each match in a tournament,” Kvitova said. “And then when the finish line comes, I’m feeling better about my game. Unfortunately I can’t just play finals, which is sad!”

Speaking of finals, Kvitova suffered a rare loss in a title match at the WTA Finals in Singapore this year – to Agnieszka Radwanska – though she did score a big win over Maria Sharapova in the semis.

She was asked afterwards what she was hoping to work on in the off-season. “The main thing I want to do is improve my health,” she said. “I have a few weeks for that, so I hope it’s going to help me, and my main goal is to be prepared and healthy for the next season. For sure that’s my biggest goal.”

Kvitova will kick off her 2016 season at the Shenzhen Open in Shenzhen, China, an International-level event that boasts twice the usual International prize money – $500,000. Radwanska will be there too.

“I’m very happy to be going back to Shenzhen,” Kvitova commented. “Last year I had a very nice time. Everyone was very kind to me, and it was also very nice to see my good friend Li Na when I was there.

“I look forward to playing there again, seeing Li Na again and hopefully winning the title this time.”

AUCKLAND, New Zealand – In two weeks, 2015’s WTA Comeback Player Of The Year – Venus Williams – will try to keep her momentum going, kicking off her 2016 season at the ASB Classic. The big question about the new year isn’t whether she’ll be able to defend her title there, though – it’s something bigger.

Can the seven-time Grand Slam champion and former World No.1 capture another major?

If the hunger she described in November in Zhuhai – where she won her third WTA title of the year – is anything to go by, the World No.7 might just get back into that Grand Slam winner’s circle again.

“Being back in the Top 10 is what every player is working for, and I’m really excited about it, but I’m still very hungry. I’m ready for more,” Williams said. “I’ve had so many experiences in tennis but I still expect a lot from myself – I’m very happy to be moving forward, but I want to continue.

“I don’t want to stop. I want to keep improving in the rankings and winning events and all that.”

After falling as low as No.137 in the world a few years ago after her Sjögren’s Syndrome lay-off, a lot of people wrote her off – and they kept writing her off as she struggled to stay in the Top 20.

But Williams has silenced the doubters before, and she’s just done it again.

“It doesn’t matter who you are or what you do, everyone is willing to write you off. No one thought I would win Wimbledon in 2005 – I was 24 years old, and in sports people always think you’re done. But you’re not done until you say you’re done. I won that title that year, and it meant everything to me.

“I believed in myself,” Williams continued. “That’s one of the trophies I keep in my bedroom because it represents believing in yourself, really just trusting your instincts, and betting on yourself.”

Williams’ first shot at her eighth Grand Slam title will come at the Australian Open. Along with the French Open, it’s her toughest major – her best result in Melbourne is one final, just like in Paris.

But there’s a new kind of aggression coming off the Williams racquet lately – she’s always been one of the most aggressive players in the game, but the years of experience have brought even more clarity.

“At this stage of life it’s about finding that happy medium of playing the percentages, being smart and using your experience, but at the same time continuing to be aggressive,” she explained. “For me, it’s innate. I would be aggressive on every single shot if I could. It’s not the smartest thing to do – you have to work the point, and you have to realize what to do on the court at the right times.

“But there’s always a part of me that’s very free, like the young player who went for every shot.”

How will the former World No.1 do Down Under? Follow all the action right here on wtatennis.com!

When Lucie Safarova upset the odds – and a couple of former champions – to reach the final of this spring’s French Open, few in the tennis world would have begrudged her this long-overdue moment in the spotlight.

In a sport where the margins between winning and losing are invariably razor-thin, there is little room for niceties. However, Safarova has always been as charming and grounded off the court as she is intense on it. Never one to short-change fans, media or her fellow players, the 28-year-old is universally loved.

There has been no doubting Safarova’s ability on court either. A regular scourge of Top 10 opponents and a major semifinalist, in the first half of 2015 the Czech finally started to add the much-sought-after consistency to her game.

While a dip in form at the start of the summer and a bacterial infection threatened to undo her earlier good work, Safarova regrouped to book a place at the BNP Paribas WTA Finals Singapore presented by SC Global. Although unable to make it out of the round robin stage in Singapore, she bounced back a few weeks later to help the Czech Republic regain its Fed Cup crown.

Now with the belief to go along with her talent, it will be interesting to see where Safarova and her larger-then-life coach Rob Steckley go next. Ill health has thrown a spanner into her pre-season training, but with relatively few points to defend Down Under, the mercurial left-hander has an opportunity to consolidate her Top 10 spot.