Finally, we have the two groups ready for the World Tour Finals and we have been gifted with another match in the Fedal rivalry.
Here's an analysis of their head-to-head stats going into the tournament (indoor results included where they've met) plus who's hot and who's not.
Djokovic-Murray: 6-4, 4-4 on hard court and 2-1 this year.
Djokovic-Berdych: 7-1, 7-0 on hard court, 1-0 indoors and 3-0 this year.
Djokovic-Ferrer: 6-4, 5-1 on hard court, 0-1 indoors and 1-0 this year.
Murray-Berdych: 1-3, 0-2 on hard court, 1-0 on carpet, 1-1 indoors and 0-1 this year.
Murray-Ferrer: 5-3, 5-1 on hard court, 1-0 indoors and 3-0 this year.
Berdych-Ferrer: 2-5, 0-2 on hard court, 0-1 indoors.
Andy Murray is obviously the hot player in this group having suffered but one defeat since the US Open. Unfortunately for Murray, he suffered that defeat at the hands of Tomas Berdych, who he trails 3-1 in head-to-head.
Their match should be close again, but if Murray plays his best, he should be able to beat Berdych. Murray starts off against Ferrer, whom he beat 6-2, 6-2 at last year's tournament.
Novak Djokovic is like an unknown entity at this point. We all remember the Novak who couldn't lose a match, but we haven't seen him recently.
Instead of resting and recovering fully, he's been playing both Basel and the Paris Masters with a nagging shoulder injury. Is the ten days between his last match at Paris Masters and his first against Tomas Berdych enough to recover?
If so, one has to like the World No. 1's chances of further advancement. He starts off against Berdych, who he leads 7-0 on hard court.
Tomas Berdych has had a so-so year, failing before the quarters in every slam but the Australian Open, where he lost to Djokovic.
However, he's been picking up steam and the last few months have seen him beat Federer, Tsonga and Murray. If Djokovic is not fully recovered, the big-serving and big-hitting Berdych could be the one to take advantage.
That said, he's only got a positive head-to-head against the red hot Murray and a negative record against both Ferrer and Djokovic.
David Ferrer made it all the way to the final of the 2007 Masters Cup, before Federer dispatched him 6-2, 6-3, 6-2. Last year, he didn't win a match nor a single set against Federer, Murray and Robin Söderling.
The diminutive Spaniard, at 5'9 he's easily the smallest player in the top ten, brings a new weapon to the World Tour Finals in terms of an improved hold game. Will it be enough against his bigger hitting opponents?
He too will have to hope for a subpar Djokovic in order to advance.
Murray wins the group and is followed by Djokovic. His vastly superior head-to-head stats against Berdych and Ferrer will be enough to see a mildly ailing Djokovic through.
Dark horse: Berdych on recent form.
Nadal-Federer: 17-8, 0-3 indoors, all at the World Tour Finals, 3-0 this year.
Nadal-Tsonga: 6-2, 2-0 indoors, 5-1 on hard court and 1-1 this year.
Nadal-Fish: 7-1, 5-1 on hard court and 2-1 in 2011.
Federer-Tsonga: 6-3, 5-3 on hard court, 4-2 in 2011 and 1-0 indoors.
Federer-Fish: 6-1, 4-1 on hard court.
Tsonga-Fish: 1-0, a five-setter at the US Open this year.
As in Group A with Djokovic, Nadal is the big unknown here. We haven't seen him play since Florian Mayer beat him in Shanghai, a week after Murray gave him a mere four points in the third set bagel in the Tokyo final.
What we do know is that Rafa wants this trophy and he wants it badly. However, there are also reports that Nadal has overworked his left shoulder during practice.
Some may expect to find Nadal rusty, but I expect him to come out guns blazing against the weakest member of the group, Mardy Fish, on Sunday evening.
His recent form is not impressive, but we saw last year that Nadal can do well on indoor hard courts, when he sets his mind to it and he is a master at peaking when it matters. I wouldn't worry too much about his shoulder until we actually see him affected by it.
Roger Federer is, along with Brit Andy Murray, the in-form player coming into the tournament. As the defending champion and with two recent wins in Basel and Paris, he's the small favourite going in to the tournament.
He's won the tournament five times, four times without losing a match, so he certainly knows what it takes. The indoor surface offers a lower bounce and makes his backhand less attackable by his fellow Big Four members as we saw last year, when he scored convincing victories against Murray, Djokovic and Nadal.
Tennis fans will be delighted to be guaranteed at least one match between Nadal and Federer. Oddly enough, this will only be their fourth match post-Wimbledon ever, the three previous all coming at the World Tour Finals.
Federer faces the toughest test of any of the big four in the opening match, when he meets dark horse Jo-Wilfried Tsonga.
Since Tsonga's 6-2, 6-2, 6-2 thrashing of Rafa at the Australian Open 2008, everybody has been well aware of his immense potential. Unfortunately for the Frenchman, injuries have kept setting him back.
This year, he's enjoyed a sustained period of play and the results started showing at Wimbledon, when he became the first man ever to claw his way back from a 2-0 sets deficit in a slam against Roger Federer.
He beat him again in Montreal, before Federer avenged the loses in the US Open and last week in Paris. Nevertheless, when he's on, nobody likes to be standing on the other side of the net retrieving service and forehand bombs.
Tsonga himself sounds upbeat at the prospect of getting a chance at Roger and Rafa and expect to beat Fish again.
Fish pulled out of Paris against Monaco with a tight hamstring and has had a less than impressive fall after a stellar year. He appears to be the weakest link and may end up being the punching ball of Group B.
Nevertheless, he should take comfort in the fact that he nearly beat Tsonga at the US Open and beat Rafa for the first time only this year in Cincinnati.
Roger wins and Rafa follows. Tsonga as a very dark horse, who could upset and replace either Rafa or Roger. A lot depends on his first match against Roger.
Semifinals and Final:
Federer versus Djokovic
Nadal versus Murray
A rematch of last years semi's, but I expect the final to be a clash between home favourite Andy Murray and marginal tournament favourite Roger Federer. If Djokovic is fit, there's obviously a chance he can go all the way.
Is it finally time for Murray to win one of the big ones? I suspect so, but I can't bet against a five-time champion, when Murray has a history of getting tight in the big finals. If Murray can regard this as just another Masters match, he'll be in good favour though.
He leads Federer 5-1 in their Masters matches and could certainly win it.
Nevertheless, I'll go with Federer in three.