Seven match points, four sets, and more than three hours and Juan Martin del Potro is through to the second round.

He made slow, purposeful and muscular progress (as is his wont) to get past Thanasi Kokkinakis 6-3, 3-6, 7-6 (2), 6-4 and suddenly it seemed like old times. And yet, a match such as this did not seem possible just 18 months ago.

Everyone knows that the crowd loves a feel-good story but on this occasion, it was nigh on impossible to work out who to cheer for. Both men are heart-warming comeback stories in their own right as both have been through more injury setbacks than seems possible.

Let us begin with the languid Del Potro. Many years ago – it seems too long to be possible – he was the next great challenge to the Big Four at the top of the rankings. Back in 2009, he was tiptoeing towards his 21st birthday and he was beating Rafael Nadal and Roger Federer to win the US Open. A star had been born. But by the beginning of the next year, that star had been sidelined with a wrist injury. 

He needed surgery on his right wrist and most of the year off to recover from it. That repair work kept him in business for a couple of years but by 2014, his left wrist had given out and after two more operations – and still no cure – he was ready to give up entirely by the spring of 2015. 

2017, First Round Highlights, Juan Martin Del Potro vs Thanasi Kokkinakis

That was when his friends and family back home in Tandil rallied round. Go on, give it one last try. One more operation. See if you can fix the wrist once and for all. And if you can’t, you can retire knowing that you have given your career every chance. So he did. And it worked. 

Last year was spent trying to rediscover his backhand but by the time he was pushing Andy Murray to the very brink in the gold medal match at the Rio Olympics, he knew he was back. When he and his team mates beat Croatia to win the Davis Cup at the end of that year, Del Potro knew he was back for good. 

And so to Kokkinakis. When Nick Kyrgios first presented his credentials on the main tour, Australia was abuzz. Here, potentially, they had a champion in the making. But what brought a bigger smile to Australian faces was that one year behind the big man was Kokkinakis, another huge talent waiting to show the world what he could do (the two team up and won the junior doubles title here in 2013). 

But no sooner than he had launched his career, becoming one of the new gang of teenagers with big ambitions and ever improving rankings, than he was felled by injury. By the end of 2015, when he was still only 19, he needed shoulder to repair the damage to his right shoulder. That restricted him to just one match in the whole of 2016 and by the time he was ready to comeback a couple of months ago, he had no ranking at all. The rankings computer had forgotten him. 

Slowly, though, those big names in the locker room are beginning to remember exactly what it was about the tall man (he is only marginally shorter than Del Potro at 6ft 5ins) from Adelaide that gave Australia such hope. In only his fifth match back on tour, he beat Milos Raonic in the first round at Queen’s Club and out on No.2 Court, he was matching Del Potro blow for blow once he had found his range. 

As the Australian voices cheered on Kokkinakis and an assortment of accents got behind Del Potro, there was not a gnat’s whisker between them. It was a story of two huge forehands (Del Potro’s was slightly bigger), two huge serves (Del Potro’s was marginally faster) and the gap in the experience between them. Sure enough, Kokkinakis hit more winners than his older, taller foe but he also racked up more unforced errors. And the key to success on any surface is to keep it nice and tidy: walloping winners are great provided they are not cancelled out by careless fluffs. 

Del Potro began the third set tie-break with an ace; Kokkinakis followed it up with a double fault. It was pretty much the story of the match: small margins, occasional opportunities and, in the end, the older wiser man made the most of them and will now play Ernests Gulbis for a place in the third round.

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