The remarkable Roger Federer has broken through for his 20th major trophy at the 2018 Australian Open.

The indefatigable Swiss legend is the first male player in history to claim 20 grand slam singles titles.

The 36-year-old second seed won a see-sawing five-setter over Croatian Marin Cilic 6-2 6-7 (5) 6-3 3-6 6-1 at a steamy Rod Laver Arena on Sunday night.

Federer raised his arms in triumph after clinching championship point following an unsuccessful challenge from Cilic.

Not for the first time, Federer showed his softer side with tears flowing freely when he looked to his players box to thank his team.

Even Rod Laver, the six-time grand slam winner, pulled out his camera to capture the moment that Federer took hold of the Norman Brookes Challenge Cup for a sixth time.

Federer is living in the moment, but he is proud of his 20 grand slam triumphs, made up of eight Wimbledon, six Australian Open, five US Open and a French Open title.

“It’s about living the emotions that I went through tonight again at the trophy ceremony, going through a tough rollercoaster match, five-setter against Cilic, who is a great player, and then getting [Australian Open title] No. 6 here, No. 20 overall,” Federer said.

“It’s just a very special moment, defending my title from last year, sort of the fairytale continues. That’s what stands out for me.

“When I start thinking about what I was going to say, every subject I touch actually is very meaningful and very emotional.

“Thanking your team, congratulating Marin, thanking the people, thanking the tournament.”

Federer settled into the match better than Cilic, who was featuring in only his third grand slam final.

The title defence for Federer seemed on track as he raced to a one set to love lead with ease in just 24 minutes.

Federer’s game was flawless in the first set, visibly showing no nerves as he dictated the points early on.

He broke Cilic twice to take a 4-0 lead.

While Federer’s exterior seem cool, he did admit to a touch of nerves in the lead up to the match that certainly did not show up in that commanding first set.

“I was so bloody nervous all day,” Federer said.

“It was eating me up inside. That’s why, when it was all over, I was just so relieved, to be quite honest.”

Cilic found his groove in the second set and it was game on.

The 29-year-old began to find his rhythm on the serve and cut out the errors that plagued his opening set.

With games on serve throughout the set, Cilic had to level the match at one set apiece through a tie breaker.

Federer regained the set advantage with a dominant third set.

Cilic had executed strong on his serve in the previous set and a half, but it broke down at a crucial time in the sixth game of the third set, allowing Federer an important break.

Cilic had become a little one-dimensional and rushed at that point of the match, relying on his power game to win points as the toll of the match and the heat in the air began to show.

But, if you thought Cilic was gone when Federer broke in the opening game of the fourth set and held a 2-0 lead, you were mistaken.

Cilic not only found a second wind, but he reeled off six of the next seven games to sensationally level up the match at two sets apiece.

It was incredible fighting spirit shown by Cilic to launch another comeback after seeming down and out.

It’s nothing more than you would expect from a player that finished the night ranked third in the world.

However, Cilic concedes the catch up tennis he played eventually wore him down.

He was happy to look at the big picture and what could be in store for him this season.

“I had a slow start in the match, losing straightaway my two service games, then catching up most of the time,” Cilic said.

“Looking overall, I’m really pleased with the performance.

“Played great tennis over these two weeks. I had tough matches, tough opponents, beating Rafa [Nadal], reaching here a final, which is definitely amazing.

“Looking at my own game, I think I improved a lot. I’m playing great tennis. That’s really exciting for me for this 2018.”

Having made a number of valiant comebacks, Cilic finally used up his nine lives.

With the crowd on his side and history there for the taking, Federer produced one of his best sets of the tournament at the crunch time.

Federer broke in games two and six of the fifth set and Cilic’s resolve was clearly shot.

Federer clinched his second consecutive Australian Open title in 3 hours 3 minutes.

After three grand slam titles in 12 months, who would back against Federer adding to his haul in 2018?

“I can’t believe it myself,” Federer said.

“I just got to keep a good schedule, stay hungry, then maybe good things can happen. Then I don’t think age is an issue, per se. It’s just a number.”

The only number that matters tonight is 20 – a number that might never be matched again in men’s tennis.