OPPONENTS of newly crowned Wimbledon champion Angelique Kerber beware - the best is still to come.

Kerber, who was sublime in dashing the fairytale hopes of legend Serena Williams in last week’s Wimbledon final, is convinced there is much more in store.

Now a triple grand slam title holder after also beating Williams in the 2016 Australian Open Final and taking the 2016 US Open, Kerber said fans could expect greater firepower going into the 2019 Australian summer.

“We’ve tried to improve my tennis from the beginning of the year to become more aggressive,” said the 30-year-old following her Wimbledon victory.

“My serve is a little bit faster than it was even last year.’’

Sydney International organisers will announce on Friday that Kerber will return to defend her crown in January.

Kerber defeated Australia’s Ashleigh Barty in the Sydney International Final earlier this year.

“I had a great week in Sydney. The draw was incredibly strong, and I was unseeded, so I had to play good tennis to get through some very tough matches,” Kerber said.

“The final against Ash was not easy, but I was able to play my game in important moments so I was really happy to start 2018 with a title win.”

The Sydney victory kick-started a tennis renaissance for former world No.1 Kerber after dropping out of the world’s top 20 in 2017.

And Kerber now sits at number four on the honour roll of active Grand Slam champions (behind Serena and Venus Williams and Maria Sharapova).

“Playing the Sydney International is always a great opportunity to face some top quality opposition,’’ she said.

“Every single match is really tough, so it’s a great way to fine-tune my game after the off-season, and also get used to the weather conditions in Australia, which are quite different to Europe at that time of the year.”

Kerber is the first reigning Wimbledon champ to take on Sydney since Garbine Muguruza in 2018.

Petra Kvitova is the last Wimbledon winner to go on to take the Sydney International title the next year, having done so in 2014-15.

Sydney International tournament director Lawrence Robertson said he is delighted to welcome Kerber back to Sydney.

“This will be the seventh year in a row Angie has played in Sydney and she has had some great results here over the years and, of course, the incredible run of form that carried her to the title this year,” Robertson said.

“Angie is a big-hitter with a wonderful personality who lights up the court when she plays. She is a huge hit with the fans here and she has now cemented her place as one of the greats of the modern game.”

The Sydney International will take place at Sydney Olympic Park Tennis Centre from January 6 to 12, 2019.