Six time Grand Slam champion Rafael Nadal's exit from the season ending championship came as a shock to some but an expected event to most tennis pundits and fans across the world. Nadal's presence in the Group B alongside his recent conquerers Soderling, Djokovic and Davydenko was a proof enough that his run at the event does not promise to take him too far. As for the others in the draw, the most significant of whom is the Swede Soderling, every single win is a bonus of sorts. Roddick's replacement at the last moments of the event's commencement, Soderling is in sensational form and has shown it in his previous two wins over Nadal and Djokovic. However, today's matches are going to be equally crucial for both Murray and Del Potro for totally different reasons.

Let's take a look at the possible equations that have risen before the start of the last Round Robin day for Group A -

Andy Murray vs. Fernando Verdasco
Head-to-Head
Murray leads series 7-1
Last Meeting - 2009 Open Tenis Valencia SF
Murray won 6-3, 2-6, 6-3

Andy Murray has a strong chance of making it to the semifinals. The reason behind the amount of conviction induced in the statement is out of the fact that the Scot has already won a match and lost a three set thriller to Federer, which means he has an additional set to his points count if the other three players come neck-to-neck in the Group standings. However, his win over Verdasco today might assure his place in the last four to a huge extent. The two players recently met in Valencia with Murray winning the match in three sets. Verdasco's inconsistent play and the inability to close out the match despite formidable leads might come in his way against the man who is known for playing percentage tennis. Amidst the electric home fans support, Murray will enter the match with a slight edge over the Spaniard.

Roger Federer vs. Juan Martin Del Potro
Head-to-Head
Federer leads series 6-1
Last Meeting - 2009 US Open Final
Del Potro won 3-6, 7-6(5), 4-6, 7-6(4), 6-2

This one is sure, rather bound, to produce some nail-biting tennis. The two players last met at the Grand Stage of Flushing Meadows, NY, where Del Potro announced the arrival of the challenger brigade in tennis by pulling a win in five dramatic sets over five time champion Federer. Having said that, it is quite evident from the past as to how Federer approaches the matches that have a scope of a 'scores settlement'. He may appear ruthless in today's match but that may turn out to be a key to success for Del Potro as well. Technically, both players are at par with each other, and if not, then they have an answer to other's strengths in their own way. It would be pretty much dependent on Del Potro as to how he succeeds in applying the mind game that is the crucial factor in today's encounter. Federer did boost his confidence with a big win over Murray, despite being on the receiver's end in most of their previous matches, and if he can translate the same confidence into his on-court mastery today, he is sure to CONFIRM his place in the last four.

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