Roger Federer is already firing on all cylinders at the Australian Open after he breezed past Denis Istomin in the first round.

The defending champion made an excellent start to his title defence on Monday with a 6-3 6-4 6-4 win, Federer barely challenged by Istomin on Rod Laver Arena.

All aspects of the 37-year-old's game worked with graceful fluidity, his serve powerful and his groundstrokes on another level to his opponent.

Add to that some deft drop shots and it was a solid start from the Swiss, and he is feeling confident that he has the tools to do well in Melbourne once again.

"I think I was hitting the ball pretty well," he told reporters. "I'm very happy with my first round, to be honest. It's been great.

"[My serve] is going so well. I think I can trust my second serve in particular. When you trust your second serve, you can go after your first serve. I have good variation, to be quite honest.

"I can be happy how I got out of the blocks from the off-season. I think that's always the most-tricky part, is how do you get through your service games time and time again, because if you don't get broken much, or hardly ever, not at all, you have so little pressure on the return games, you can really try out different things.

"I started to feel midway through the first set that it was going to be difficult for Denis to get into my service games. That relaxes you from the baseline. Then good things really happen."

The defending champ sails into round two @rogerfederer defeats Denis Istomin 6-3 6-4 6-4 #AusOpen pic.twitter.com/ySoZTL0qfI
— ATP Tour (@ATP_Tour) January 14, 2019

Federer finished the match with 52 winners, some of which came when he began to mix his game up to stop any chance of an Istomin comeback.

"I feel like I'm volleying really well. I feel really comfortable at net," he added.

"I think also mixed doubles [at the Hopman Cup], to be quite honest, helped me because I served and volleyed in the mixed doubles all the time and spent a lot of time at net.

"I've been feeling good at the net for quite some time now. I think the transition with the sprints and stuff, I feel really good about it.

"My body is in good shape. I think it always depends on who you're playing a little bit, depending on how they return or well, it's better or not to serve and volley against certain players.

"Today I didn't feel the super urge to do it. I only did it in selective times. Look, we'll see who I play and if it can be of good use. I'm happy I have it in the bag."