"That is a gorgeous tennis point," says Leon Smith over on 5 live Sports Extra. And who am I to disagree. 

Roger Federer is grooving away now, moving those hips and twinkling those toes. He pulls and pushes Melzer across court, guiding a beautiful volley past his Austrian opponent for 30-0. And another outrageous forehand winner - down the line - tees up three break points for Fed....

Another blink-and-you'll-miss-it service game from the Swiss maestro. A perfectly-executed smash sets him on the way, before a couple of unforced errors are Melzer's undoing. Hold to love.

Image source, Reuters

Fourth seed Stan Wawrinka is into his fifth set against Slovakia's Martin Klizan, and it's still neck and neck. Every time Wawrinka gets his nose in front, Klizan bites back with a fine forehand. They're rapidly approaching the three hour mark.

Image source, AP

Wow. A super forehand winner from Jurgen Melzer gives him breathing space, before another goes long to give Federer a sniff at 40-30. Melzer dangles the chance under Fed's nose, swiping it away when a deep return leaves the Swiss unable to control his effort and the ball goes long.

Melzer, the world number 296, is a break away from the first set....

Problem? What problem? Roger Federer rattles off another service game - inside 60 seconds - to tie up this intriguing opening set. A thunderous ace down the middle leaves Melzer wafting and wondering what might have been. All square.

What a response. Roger Federer claws his way back on serve instantly. 

Federer is pushing his fellow 35-year-old all the way, taking him to deuce after Melzer goes within a point of the game when a 25-shot rally ends with the Swiss overcooking a forehand.

Melzer blows his chance when he scoops a forehand into the left tramlines, then a poor drop-shot into the net coughing up his first break point of the match.

Melzer survives one - but can't survive a second. Another badly-executed drop-shot crashes into the tape.

Leon Smith
Great Britain Davis Cup captain on Radio 5 live Sports Extra

Melzer has started well. He has served well and held them easily. he is moving well and being aggressive with the ball. A good start.

Look what we have here. The Rod Laver Arena crowd don't know what to do. This is not what they wanted to see. Jurgen Melzer has a break point when Roger Federer sticks a backhand volley into the net from close range.

And the Austrian snaffles it when he bends down, almost on his haunches, to dig out a baseline backhand which beats the 17-time Slam champ. Melzer is pooping the party. 

Image source, Reuters

Leon Smith
Great Britain Davis Cup captain on Radio 5 live Sports Extra

I keep looking at Roger's footwork and it is spot on.

Now then. Roger Federer ramps up the pressure, forcing Jurgen Melzer into errors - and into deuce. But the left-handed Austrian responds splendidly, arcing a service winner down the 'T' to leave Federer wafting at thin air.

Advantage. And the world number 296 seals the hold when - after a bit of confusion and the help of technology - Federer finds out his return is too long.

Stan Wawrinka, speaking in French, has a moan at the umpire about someone shouting out during a rally but the point stands and Martin Klizan is 30-15 up. The Slovakian powers down an ace and follows up with a slam-dunk smash on set point and we are level at 2-2. Swiss Wawrinka, the 2014 men's champion, is still chuntering as he walks back to his seat.

They are rattling through these games. The receiver finally gets on the board when Jurgen Melzer thumps a beauty of a forehand winner for 15-15 - that's as good as it gets for the Austrian. Federer has the Laver crowd drooling with a sumptuous forehand down the line, his contorted body seemingly defying physics to reach and return it.

For those of you interested in every minute detail of Roger Federer's life - and there are plenty of you out there - you might want to know what he's pulled out of the wardrobe. A natty , monochrome number. A white shirt, patterned with thin black lines over the chest and sleeves. Looks a bit like my car windscreen after I've attacked it with an ice scraper.

Anyway.... Another hold to love for Melzer ends when Federer cracks a backhand into the net.

Much better. Roger Federer fails to find the target with his first serve of his comeback, eventually finding some rhythm in his feet to race into a 40-0 lead. A service winner seals the deal.

Image source, EPA

Well that was anti-climatic. Roger Federer shanks one, mishits another, then can't near a couple more. Possibly one of the Swiss maestro's worst returning games ever. Jurgen Melzer holds to love.

Poor Jurgen Melzer. The 37-year-old Austrian, who came through three rounds of qualifying, barely has a fan in the place. I bet even his other is cheering on Fed.

Melzer to open up... 

Leon Smith
Great Britain Davis Cup captain on BBC Radio 5 live Sports Extra

How relaxed does he look? Most people try to get the body moving - he doesn't. He is so cool. He's ready.  

With the superlatives that have routinely been used to describe Roger Federer over the past two decades, one wouldn’t be surprised to see him reincarnate as a Swan Lake dancer once he puts his racquets into the retirement cupboard. Grace, poise, elegance. 

So it was such a shock when the great man pulled off his robotic mask to reveal... he actually is human. After so many years avoiding serious injury, the 17-time Grand Slam winner did his knee in - running a bath for the kids. How normal.

That ruled him out of the remainder of 2016 following his Wimbledon semi-final defeat by Milos Raonic. Now, after a couple of looseners at the Hopman Cup, it is back to business.

I hope they were handing out earplugs at the turnstiles. The noise inside Laver is almost deafening as Roger Federer, looking as immaculate and - frankly - damn cool as ever, strides out for his first competitive match since Wimbledon. Amazing reception.