Like Raonic, Murray holds to love, but the Scot was made to move around a little bit more - it's hard to knock one past a 6ft 5in young whipper snapper.

Murray has so far won 71% of points on his first serve and Raonic has won 91%.

The Scot was very dominant in that stat against Stan Wawrinka on Friday.

Ross McD: Murray chews up big servers, even ones with little bit more to their game like Raonic. First set tight, second set easy.

Possibly having a tougher time than some might have envisaged

Image source, Getty Images

His serves are pretty bruising. Murray isn't chasing any of these because Raonic is making sure he can't - accurate and fast.

The Canadian holds to love.

Now then. A glimmer for the outsider. It's 30-30 after Murray's groundstroke from the back of the court is fractionally inaccurate.

But the Canadian presents him with a gift by firing a forehand into the net. Murray will surely seal this now?

Nope. Raonic produces a great winner - it's deuce.

Wow! The 25-year-old 6ft 5in giant opens up and lashes a forehand wide of the reach of Murray.

Break point. 

Fault. 

Second serve. 105mph and heavy - which Raonic can only get the frame of his racquet to.

Murray finally holds with two good serves.

...had this fella and his son turn up to watch him play on Thursday. So who wins the celebrity fan top trumps game?

I've not yet spotted any A-listers (and those lower down in the alphabet).

On Friday, Oscar winner and stage actor Kevin Spacey rocked up to watch Murray play Wawrinka.

Raonic snatches at a forehand at the net - it's called out. The world number four challenges but the replay shows the ball to be out. 

He makes amends for that poor placement by stretching Murray in the next point - 15-15.

Raonic eventually holds again, but he will be concerned that the world number one is getting his racquet onto almost everything that's being thrown at him.

Image source, Reuters

Andy Murray's mum, Judy, is in the BBC TV studios with presenter Sue Barker, and talked about how her sons are both poised to finish the year as world number ones. 

Jamie and partner Bruno Soares have already sealed their place at the top, and will end the year as the number one doubles team in the world. 

As we know, Andy has to ensure he either betters or equals Novak Djokovic result to keep hold of his number one singles spot. 

"Andy is a real geek with tennis," their mum says, before adding that her eldest son seems more concerned with his brother's tennis career than his own. 

"I think he knows what's going on in his world, but he's absolutely on top of everything Jamie is doing. 

"You never ever hear them comparing what they have done." 

Andy has previously said: "I think we're probably each other's biggest fans. Neither of us would ever have expected this growing up."

It's another hold to love for Murray. He seems in a very cool and confident mood and already has Raonic darting around the court.

Will the Canadian get a chance to dictate?

Raonic races to a 30-0 lead before messing up at the net allowing Murray to pass him.

Out of the blue the Scot produces a great backhand pick-up from the back of the court to pull it level.

However the Canadian keeps cool and holds with a heavy serve down the T.

Murray wins the service game to love. It was that easy.

Raonic was dancing about on the baseline. Nerves? This is still a relatively new experience for him - a semi-final at a major championship.

Piers Newbery
BBC Sport in London

There was a real air of tension around the O2 on Friday when Murray took on Wawrinka, but the world number one stepped up his game considerably to put the Swiss away in straight sets.

It might be because of his thumpingly good record against Raonic but you're hard pushed to find anyone who thinks Murray will struggle today. Well, the Canadian ran Djokovic close in the group stage and has his own rankings target, with a career-high number three in his sights.

Playing indoors, on a quick surface, over the shorter best-of-three, must add up to the best possible conditions for Raonic to test Murray.

Chris Goldsmith: May not be as big as the ATP finals! But Marcus Willis has just won the ITF Futures title in Kuwait. 18 ATP points

There is always a place in our hearts for Willis

In case you didn't know, Andy Murray's big brother Jamie is guaranteed to be one half of the world's best doubles pairing, along with partner Bruno Soares, at the start of 2017.

Defeat for Nicolas Mahut and Pierre-Hugues Herbert at the ATP Finals on Friday confirmed their status as top of the doubles rankings.

That's three Grand Slams (he won the Wimbledon mixed doubles with Jelena Jankovic) and a number one spot. That all sounds a little familiar...

Both players are out on the empty swimming pool of a court at the O2.

Murray wins the toss and elects to serve first. It all seems cordial with umpire Dumusois so far.

So the umpire today is Damien Dumusois.

Back in April, Muzza was involved in a 'heated exchange' with the Frenchman during the Monte Carlo Masters semi-final against Rafa Nadal.

Murray said: "It's fascinating what you let some of these guys get away with", in response to Nadal taking a long time between points.

Dumusois then alleged that the Briton twice lofted the ball towards him.

"You have zero respect for me," said the umpire. "Don't just make stuff up," Murray responded.

Andy Murray on Raonic: "I think he's played very well so far in this event. It will be tough, he's got a huge serve.

"Obviously I'm looking forward to playing him. It's an amazing stadium, an amazing atmosphere." 

Image source, Getty Images

So Milos Raonic. The oh so genial Canadian.

The 25-year-old has leapt from 14th to fourth in the world in a year.

He reached the Queen's Club and Wimbledon finals this year but lost to Andy Murray on both occasions.

In actual fact, he's faced the world number one six times this season and lost on each occasion. He's essentially going through what Murray went through a few years ago - get to the semis then lose to Fed/Djoko/Nadal.

He's won one title this year, in Brisbane back in January when he defeated Roger Federer.

Victory over Murray today would surely rank as one of his greatest.

The Hairy Bikers will be making way soon...