For one uncomfortable month, in the aftermath of the most shocking collapse of his career, the discourse around Jannik Sinner focused on his lack of durability. Not only was he so vulnerable in remotely warm conditions, but to many his five-set record of six wins and 12 defeats was unworthy of a player of his stature.

It was only fitting, then, that Sinner immediately found himself embroiled in another fifth set on his return to the match court. This time, the world No 1 kept his composure and held firm physically at the climax to recover from two sets to one down against a courageous challenger in Miomir Kecmanovic, opening his title defence with a 4-6, 6-3, 6-7 (6), 6-2, 6-3 win on Centre Court.

The last time Sinner competed things spiralled out of control. He had arrived at the French Open more heavily favoured to win the title than any player in recent years other than Rafael Nadal at his peak. His tournament instead ended with him losing 18 of the final 20 games after leading Juan Manuel Cerúndolo 6-3, 6-2, 5-1 in the second round. He has spent much of the weeks since then undergoing tests and adapting his work on the court in an attempt to figure out how to ensure that such an event never happens again.

For months, many of Sinner’s beaten opponents would liken his ruthless style to that of a robot or machine, and so Paris at least showed Sinner to be human and it underlined how challenging it is for the Italian, like all others, to constantly produce his best tennis regardless of the circumstances. Sinner had opted not to compete in any grass-court tournament before Wimbledon, so his game was also coated in rust. From a deficit of two sets to one, he did well to compose himself and find a path through.

“I always enjoyed this moment because what emotions I felt last year, it was the first time that I felt in this way, in a very happy way,” Sinner said. “Coming back here and opening and play on Centre Court, this year was a year where nobody practised on it before, so it was brand new. Mentally, you know it.

“It has been an amazing, amazing day for me to feel this way at least once in my life. Yeah, I think I handled the situation still quite well. Yeah, it was very nervy, but very happy that I found a way today.”

Sinner looked tense and devoid of confidence from the opening set. After a series of uneventful service holds, he was leading 40-0 on his serve at 4-4 when he fell apart. Sinner hit his first two double-faults on consecutive points from 40-30, then a rancid forehand error on break point, his fourth consecutive unforced error, closed out the game. In the blink of an eye, Kecmanovic had won nine points in a row to win the set.

A shaky opening set in a best-of-five match is hardly a disaster, particularly in Sinner’s first match of the grass-court season. However, even after taking the second set, Sinner struggled to strike the ball freely. His error count continued to rise steadily and he played tentative, tight tennis in the decisive moments. His confidence was probably not helped by the bad fall he suffered at the beginning of the third set, which led to the trainer on his right foot becoming soaked in blood.

Afterwards, Sinner reassured his audience that he felt fine despite the very visible sight of blood on his shoe: “I’m good. It just seems much worse than it is. Actually, very surprised that they let me keep playing because, you know, all white, it turned into a little red. But I didn’t want to disturb Miomir. I thought we both had a good rhythm, it was a great match from both of us so I didn’t want to take any time.”

While Sinner was tight, Kecmanovic played some bold tennis, particularly in the final minutes of a dramatic tie-break. With a potential upset becoming increasingly realistic, the Serb forced himself on top of the baseline, taking the ball early and redirecting brilliantly off both ground strokes to establish a lead of two sets to one.

Sinner took a short break between sets and when he returned, he gradually found his way again. He served brilliantly from the beginning of the fourth set, which allowed him time to regain rhythm and timing behind his ground strokes. The Italian was also unusually demonstrative, pairing his fist pumps with barks of “let’s go” that were audible in all corners of Centre Court. He ended the match in full control, dominating from the baseline and demonstrating the service improvements that will bode well on the grass by firing down a career-best 31 aces, while his confidence gradually returned.

“I was a little tight at the beginning, I didn’t play my very best,” he said. “I tried to get into it, it was my first official match on grass. This also is very important – happy that I turned it around because the third set was a very tough one to swallow.”