When Alexander Zverev was struggling through five setters at the French Open last year – where a quarter-final appearance is his best performance to date – he had received unequivocal encouragement from Rafael Nadal.

Asked about struggles in a press conference, a no-nonsense Nadal cross-questioned the reporter asking if he was still in the tournament or no?

“It’s sport. Everybody suffer, everybody have problems, and it’s normal that you have challenges every day… But he’s still in the tournament, and, you know, it’s important in the Grand Slams win. The first matches doesn’t matter the way,” Nadal said.

Nadal’s encouragement is just one more in the pile of evidence about how highly-rated Zverev is. Yes, the frequent five-set took a toll on his body at Roland Garros and he crumbled in the quarter-final to Dominic Thiem. His showing at the next two Grand Slams was not any better as he succumbed to the unlikely opponents in the third round – Ernests Gulbis and Philipp Kohlschreiber. Perhaps it is the pressure of expectations, the format or simply inexperience, Zverev has not done well at the Majors in his short career so far.

But heading into the first Grand Slam of the 2019, the fourth seed is marked as the heir to the throne after his superlative end to 2018.

In such a scenario, his 7-6 (7/5), 6-4, 5-7, 6-7 (6/8), 6-1 win against Jeremy Chardy in the second round of the Australian Open looks worse than it possibly is.

Yes he spent much longer on court than was needed and yes he could have been smarter. Multiple times through the three-hour-and-46-minutes match, the 21year-old has chances to go for the kill. Instead, he allowed himself to be pushed to the brink in a match that ended well past midnight on a court where there was another to come.

But the scoreboard doesn’t tell the full story: His five-setter in Australia was nothing like the one in France. In Melbourne, Zverev displayed his grit and relatively new-found composure. He kept his cool even when things didn’t go his way, instead of crumbling as he tends to.

Why was this five-setter any different?

For starters, he had Ivan Lendl in his box and has now spent enough time with the Major-winner-maker to curb his erratic performance, especially under pressure. And then the experience of having beaten Roger Federer and Novak Djokovic to win his biggest career trophy two months back at the ATP Finals.

Fresh legs, cool head

The 31-year-old Chardy, ranked No 36 in the world, can be a dangerous floater and always had the potential to show up in the big moments.

Zverev started with a commanding 4-1 lead in the first set, but lost his concentration as Chardy pushed for a Tiebreak, saving a set point. The German regrouped to clinch the Tiebreak and then went on to take a 2-0 lead.

It should have been smooth-sailing from there on but the Frenchman broke at the death to take the third set, after Zverev failed to convert four break points at 5-5.

He went on to save three set points in the fourth set to force a Tiebreak, but could not convert the match point he had. With an end like that, the decider could go either way. But encouraged by his box who were on their feet – his father and coach Alexander Zverev Sr, brother Misha and Ivan Lendl, Sascha used his much younger legs compared to his opponents and cool head to go double break up, right at the stroke of midnight.

Knowing Zverev’s proclivity for collapses, even a 4-0 lead was no guarantee as the fifth game went to deuce five times, with silly errors including a double fault. But he dug in with a solid forehand and sealed the game with an ace down the middle to make it 5-0. And after he clinched it, he looked more relieved and drained.

It helped that Chady looked knackered and had trouble moving, a chink that Zverev exploited by hitting deep. It was clever tennis, keeping his wits after brief lapses in concentration cost him time.

The other, very striking aspect of Zverev’s win was his reaction after. He warmly embraced Chardy, his friend and teammate at Laver Cup, and continued applauding him as he walked out. In the on-court interview, he had wonderful words about his last and next opponent – Aussie wildcard Alex Bolt, whose story Zverev recounted.

This, along with his tennis, points to how Zverev is maturing as a player. What toll this will battle take on his fitness – which was less than 100% last week – remains to be seen. But mentally, this will be a huge boost for the fast-evolving youngster.