Whether it be because players are turning up at the US Open without being at full fitness or because the overbearing heat and humidity in New York has taken its toll, 14 matches across the first four days of action at Flushing Meadow have finished prematurely because of a retirement.
This in itself could open up various questions within tennis about players refusing to pull out in advance because of the capacity to lose first-round prize money or a possible need to shorten matches on account of the weather or the impact playing for hours has on the body.
Andy Murray is showing that physical fitness is just as important as ball striking, having been on court approximately six hours so far to beat Nick Kyrgios and Adrian Mannarino respectively.
Murray will need to win seven matches at Flushing Meadows to become the US Open champion for a second time, but the big question is whether this is possible having been involved in such lengthy showdowns in the early rounds?
It is 5/1 that Murray does win the US Open and Rafael Nadal should be his rolemodel if he is to overcome any early fatigue to lift the trophy.
To put into context the disadvantage Murray currently finds himself in, his two main rivals for US Open victory – Novak Djokovic and Roger Federer – haven’t played for six hours between them in reaching the third round.
While Murray has dropped 33 games and three sets in the opening two rounds, Djokovic has lost only 10 games and Federer nine.
It’s no surprise that the majority of men’s Grand Slam winners in recent years did so on the back of making light work of their opening two matches.
But Stanislas Wawrinka recovered from dropping a set to Dusan Lajovic in round two of this year’s French Open, while Djokovic gave up a set to Radek Stepanek in his second-round tussle at Wimbledon in 2014.
What is significant though is that Murray has already gone through a five-setter, with his comeback over Mannarino being the eighth time in his career that the Scot has battled back from 0-2 down in sets to win a tennis match.
The last player to make similarly heavy work of an early Grand Slam clash was Nadal, when needing five sets to beat John Isner in his first match at the 2011 French Open, where he found himself 2-1 behind at one point.
Nadal is also the last player to win a Grand Slam having dropped sets in both of the opening two rounds, doing so at the 2013 French Open when making slow starts against Daniel Brands and Martin Klizan.
Murray is now faced with a challenging but not insurmountable task to win the US Open, although another hard-fought victory over Thomaz Bellucci in the third round is certainly not what the doctor ordered.
The good news is that the number three seed did beat the Brazilian in straight sets in their only previous encounter, albeit back in 2011.
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