Tim Smyczek wouldn't bat an eyelid if Rafael Nadal pulled on roller-skates and replaced his usual racquet with one double the size.

The American looks totally unfazed by the situation and serves out to love with a thumping ace.

This is the bit where he is supposed to fold and we all congratulate him on a fight well fought.

This bit doesn't look like it is in Smyczek's script.

Image source, AP

And after two ding-donging games to open the deciding set, we have had two more straightforward ones to follow.

Rafael Nadal holds to 15, but as the Spaniard trots to the other end the crowd are not singing his name.

"Timmy! Timmy!" is the chant from large part of the Rod Laver Arena.

No sign of the winners running dry off Tim Smyczek's racquet. A forehand winner flows into a backhand winner and then an ace.

A hold to 15 and he strolls over to his chair and casually shakes up a bottle of isotonic as a reward.

A cracking stat from David Law on BBC Radio 5 live sports extra by the way: Nadal has won more Grand Slam titles (14) than Smyczek has played Grand Slam matches (13).

Put that in your pipe.

Mr H:, external Great to see great players getting pushed all the way by lesser known players. Good for the sport!

Leon Smith
GB Davis Cup captain on BBC Radio 5 live sports extra

"Smyczek will have to play relentless tennis. He'll need point after point of top-class tennis and that will be very hard to do against someone like Nadal."

The game only gets underway after a minute or so of faffing around with a camera that is buzzing around in Tim Smyczek's eyeline behind Rafael Nadal's serving arm.

It was worth the wait. Without the distraction, Smyczek absolutely smites a forehand returns for a clean winner and 30-30.

Not a flicker of celebration from the American. He is saving all that for a possible win.

Smyczek unloads the full payload in the next two rallies, walloping everything within reach and it is enough to crowbar the deuce door open.

Nadal can dance to this mix though. Two thumping forehands of his own close out the game.

Two slug-fest games to open the decider and that is just how we, and the Rod Laver crowd, like it.

Leon Smith
GB Davis Cup captain on BBC Radio 5 live sports extra

"Nadal is certainly moving better now and his forehand is looking more potent, but maybe this is Smyczek's moment."

A beautifully weighted backhand volley from Tim Smyczek wins one rally. A blur of a return from Rafael Nadal on the next.

Plenty of quality still out there despite the late hour and the physical demands.

Another pearler from Nadal, a backhand down the line, brings up deuce.

The Spaniard runs around a forehand and fires a shot down the same trajectory on the next rally for a break point.

Tim Smyczek has shown titanium nerves though and lures Nadal into the net as he keeps hitting depth despite the scoreline.

A sledgehamer forehand from the American recovers another and he finally closes the lid on the game with a big serve.

A chance missed for Nadal, but there will be more. Can Smyzcek create his own opportunities?

Rachel Innes:, external The stats between Smyczek and Nadal are interesting. Fifth set match with a Slam champ is virtually unknown territory for Smyczek.

• Rafael Nadal has won 710 matches in his career; Smyczek 23 matches

• Nadal has won 16 five-set matches; Smyczek has only played three (won two)

Image source, EPA

This bathroom is getting more use than a Portaloo on the last day of Glastonbury. Tim Smyczek excuses himself ahead of the start of the decider.

Leon Smith
GB Davis Cup captain on BBC Radio 5 live sports extra

"Nadal has such resilience. He's facing adversity and isn't feeling very well but he managed to compose himself. He knows how to manage his time between points and conserve his energy. That comes from experience. Smyczek hasn't got that experience, especially over five sets, and he'll need to lift his game again."

Tim Smyczek has a good one-two punch tactic worked out - returning deep, cramping up Rafael Nadal and then pinging down the line into wide corridors of space - but it is not enough to save him.

Rafael Nadal stretches him out wide with a serve at 40-30 and Smyczek flings himself left but can't block back.

We are into a fifth. And it is probably advantage Nadal after he steered himself home in the fourth and started to look a little less green.

A bit of non-event of a game.

Tim Smyczek holds to love as Rafael Nadal, who has been looked a little better health-wise after all that deep breathing and head-between-the-knees stuff earlier in the set, saves himself to try and serve out successfully.

Rafael Nadal does just enough to keep his nose just ahead. He closes out with a precise serve out wide that Tim Smyczek takes a look and realises is already beyond him.

Which will give out first? Rafa's health or Tim's stamina?

Nadal did not have to do much to move ahead in the fourth set as Smyczek loses his groundstroke mojo, planting a couple of forehands into the net.

The Spaniard fires elegantly across court to seal the game though.

This could get ugly. Closing-time pub-car-park massive-airshot-haymakers ugly as these two battle their bodies and try and stay aggressive.

David Law
BBC Radio 5 live sports extra commentator

Image source, AFP

"You have question marks as to how seriously ill or hurt he is. There's something wrong but how bad is it and what is it? We don't know the answers. Can he bounce back? Even now I still think Nadal can win this match. It's been a strange day, what with Federer being stung by a bee as well as Sharapova's match."

A cruisey hold from Rafael Nadal as Tim Smyczek's rather casual slice forehand return floats long.

He will have to mine some deep reserves of grit to get out of this spot of bother though.

One Rafa fans in the stands - a lady in her mid-20s - is wearing a particularly glum expression along with supportive facepaint and a headband bearing her hero's name complete with little hearts at the apex of the 'A's.

Leon Smith
GB Davis Cup captain on BBC Radio 5 live sports extra

"Nadal is struggling again. He didn't move to one of those serves. He didn't even attempt to stretch for it."

Image source, AP

Rafael Nadal may have that trademark lasso forehand, but Tim Smyczek has some weapons of his own.

Two aces - his 11th and 12th of the match - come along with an increasingly familiar jumping backhand swat and a sublime pick-up winner from the back of the court. He holds to 30 and Nadal is spending long periods between points slumped over and breathing deeply.

I would get the doctor back on soonish if I were him.