Ever since a problematic wrist injury threatened to bring a premature halt to his blossoming career, Juan Martin del Potro has failed to reproduce the kind of form that saw him win the US Open in 2009.
The 25-year-old has continued to claw his back up the ATP world rankings, where he currently resides in fifth, but the Argentine has fallen short in his attempts to reach a second Grand Slam final.
After a positive end to 2012 saw him reach the last four of the ATP World Tour Finals, Del Potro was quietly fancied to impress at the Australian Open, but after coasting through his first two matches, he was the victim of an inspired display from France's Jeremy Chardy, who withstood Del Potro's fightback to win 6-3 in the deciding set.
However, Del Potro kick-started his year with success in Rotterdam, winning the tournament without dropping a set, but he slumped to a quarter-final defeat the following week in Marseille as he struggled to find consistency with his game.
Del Potro arrived in Indian Wells for the first Masters Series event of the year without being considered a major challenger for the title, but he surprised the American crowd with two powerful performances against Andy Murray and Novak Djokovic before losing in three sets in the final to a resurgent Rafael Nadal.
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Again, the signs were there that Del Potro was ready to become a frequent threat over the coming months, but he endured a disastrous clay court campaign, failing to reach the quarter-finals in three tournaments before withdrawing from Roland Garros with a viral infection.
The enforced break allowed Del Potro to recharge his batteries ahead of the grass court season in England, making his return with a quarter-final exit to Lleyton Hewitt at Queen's.
The Argentine arrived at Wimbledon with an outside chance of reaching the final after being drawn on the opposite side of the draw to Nadal, Murray and Roger Federer, but the prospect of a semi-final showdown with Djokovic lay in wait if he could overcome David Ferrer.
Del Potro's chances looked bleak early in the match when he suffered what appeared to be a serious knee injury, but after lengthy treatment, the Tandil-based player powered his way to a straight-sets success over the Spaniard to earn his shot against the world number one.
The pair put on arguably the match of the year in front of a packed Centre Court crowd, with Del Potro showing remarkable determination to fight back from match points down to force a fifth set, but he was ultimately outlasted by his Serbian opponent.
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Del Potro endured a mixed few weeks on the American swing. He opened up the stretch of tournaments with victory in Washington, and while he would have been pleased with a semi-final showing in Cincinnati, early exits at Montreal and the US Open hindered his attempts to rise up the world rankings.
However, the world number seven remained in touching distance of rising two places up the standings, and a tournament triumph in Tokyo saw him move past Federer and Tomas Berdych.
A profitable week in Shanghai soon followed, defeating Nadal on the way to a final loss to Djokovic, before a return to Europe saw him record success over home favourite Federer in his home town of Basel.
October had proven to be Del Potro's strongest of the year, but with an ATP World Tour Finals place in his sights, Federer sought revenge for his loss in Basel, and he ousted the South American to make the last eight.
The two would also meet in London with a place in the semi-finals at stake, but despite taking the opening set, Del Potro couldn't withstand the ability of Federer and the support of the English crowd as he eventually fell short in three close sets that brought his year to an end.