Before injury, Juan Martin del Potro was nearing uncharted territory

WATCH—Juan Martin Del Potro's hurts his knee in Shanghai:

After playing his first full schedule in years, Juan Martin del Potro earned a place in the field at the ATP Finals in London for the first time since 2013. A fall in Shanghai has left him with a fractured kneecap, but no matter if he ends up playing London or not, his 2018 season has been a huge success.

Over the past several years, Del Potro has had to pace himself over the course of the season after dealing with multiple wrist surgeries. After missing the bulk of 2014 and ’15, he gave himself a later start to the year in 2016 and ’17, which enabled him to steadily build his ranking back up.

This year, his preparation for the Australian Open included a trip to the final in Auckland. Though he fell early in Melbourne, his result still marked a triumph of sorts as he competed in the tournament for the first time in four years.

The event in Delray Beach, which had been his starting point the past two years, didn’t go as expected, but from there, Del Potro caught fire, culminating in the first ATP Masters 1000 title of his career in Indian Wells.

As the tour turned to the spring clay-court stretch, his lead-up results to the French Open were disappointing. In Paris, though, Del Potro showed the importance of having a short memory as he stormed to the semifinals, his first final-four showing there since his epic five-set loss to Roger Federer in 2009.

Rafael Nadal halted Del Potro’s Roland Garros run quite convincingly, and it was the Spaniard who stopped him again at Wimbledon in one of the best Grand Slam matches of the year in the quarterfinals.

In his return to the hard courts, Del Potro would reach the final in Acapulco and the quarterfinals in Cincinnati, results that helped set the stage for one of the feel-good stories of the summer.

Entering the US Open at a career-high ranking of No. 3, the 30-year-old reached his first Grand Slam final since his victory in New York back in 2009. He dropped only one set on his way to the championship match, which he lost to a resurgent Novak Djokovic.

Then in Beijing, Del Potro marched to the final, where he was upset by Nikoloz Basilashvili. The world No. 4’s campaign in Shanghai got off to a solid start, but then disaster struck. While down a set to Borna Coric, the 6'6" hurt his knee in a tumble to the ground.

An announcement from his representatives said that Del Potro has a "fracture of his right patella bone" and that "in the coming days, the doctors will evaluate the recovery process needed to return." He was scheduled to play Basel and Paris before London, but the end of his stellar 2018 season may be in jeopardy.

No matter what happens next, even if he has to pull the plug early, the “Tower of Tandil” has still had his most successful season in five years. With more milestones well within his reach, if not this fall then in 2019, here's hoping he makes a full recovery and can be ready to push himself to even greater heights.

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