Roger Federer
Federer won his fifth Australian Open title in 2017 Reuters

The 2019 edition of the Australian Open will debut a new fifth set deciding system and former champions, Roger Federer and Angelique Kerber have opined on the new method.

Till last year, the Australian Open had a traditional full set in all of its set but from this edition, the decisive set will have a tie-break. If the fifth set is tied at 6-6, the match will proceed to a tie-breaker wherein the first player to reach ten points – instead of the traditional seven – will be declared the winner.

Defending champion Roger Federer was asked about this rule change during the Hopman Cup in Perth and he felt that the marathon matches will be missed.

"We will miss the 70-68 in the fifth, so that's a pity," he said, referring to the score of the famous final-set marathon between John Isner and Nicolas Mahut at Wimbledon, 2010.

On a personal note, the six-time Australian Open winner said, "I am okay with any format really. Thing is, when it goes to six-all in the fifth, you've had plenty of chances to win it, or lose it, so from that standpoint how it ends is secondary in my opinion."

Kerber, who won her first grand slam at Melbourne in 2016, said that she had no idea whether she liked the new rule.

"I like physical matches and if you come here to Australia you have be really fit. With the weather, the conditions, it's really hot and humid and you have to ready for that," she said.

"I have no idea if I like (the new rule) or not, we will see."

But the woman ranked number 2 in the world added that she understood the other side of the coin too.

It might be easier because you can save energy, on the other side it is a tradition to play the advantage set. Let's see how it works this year."

This rule change now means that all the four grand slams will have different rules in 2019. The Australian Open will have a fifth set tie-breaker at 6-6; the Wimbledon will have a fifth set tie-breaker at 12-12; the French Open will have no tie-breaker while the US Open will have a traditional fifth set tie-breaker.

Talking on this, Federer joked about the potential confusion the four different rules may cause.

"The funny thing is we have four different formats in four Slams, so it is important to remind yourself what's going on and which one it is," said Federer.