World number one Jannik Sinner survived an almighty scare as he began his Wimbledon title defence with a five-set comeback victory over inspired opponent Miomir Kecmanovic.

One month on from a seismic second-round loss at the French Open, four-time major winner Sinner recovered from an error-strewn start and an awkward fall to overcome his 50th-ranked opponent 4-6 6-3 6-7 (6-8) 6-2 6-3 after a tense three and a half hours.

Sinner opted against contesting a grass tournament in the lead-up to Wimbledon, with this his first match since an extraordinary collapse against Argentine Juan Manuel Cerundolo, whom he had led by two sets and 5-1 at Roland Garros.

Having appeared to physically shut down in the stifling Paris heat that day, Sinner’s durability was thoroughly tested by Kecmanovic, and he was fortunate to escape relatively unscathed after a moment of genuine concern on Centre Court.

There were gasps in the crowd when Sinner slipped behind the baseline during the third set and took time to return to his feet, with the umpire heading over to check on him.

Blood was also seeping from the Italian’s shoe during a must-win fourth set, which he later explained was caused by a problematic toenail.

Sinner had won just one of his past nine matches that had gone to a fifth set – but he raised his level when it truly mattered to stave off Kecmanovic and avoid becoming only the third defending Wimbledon men’s champion to lose in the first round.

Sinner, contesting the opening match on Centre Court after beating Carlos Alcaraz last year to win a first Wimbledon title, said: “I tried to stay there mentally, [but] also trying to enjoy the moment.

“Coming here, [playing in the] opening match on Centre Court, it’s a huge privilege.

“It has been an amazing, amazing day for me to feel this way at least once in my life.

“I think I handled the situation still quite well. It was very nervy, but I’m very happy that I found a way today.”

With the continued absence of injured main rival Alcaraz, Sinner once again began a major as the strong title favourite.

Renowned for his devastating precision, Sinner made an uncharacteristic 10 unforced errors in the opening eight games, but saved two break points to avoid an early setback.

However, back-to-back double faults and another miss from the Italian gifted Kecmanovic his breakthrough in the ninth game, and the Serb did not flinch as he served out the first set to love.

Sinner – having won all four previous meetings with Kecmanovic, including a straight-set win for the loss of just seven games here two years ago – was below his clinical best but kick-started his fightback with an immediate response in set two.

Reducing his number of errors, and winning all 14 points behind his first serve, Sinner levelled the match – but only after withstanding a break point as Kecmanovic continued to probe.

Eyeing his first victory over a top-10 player at a major, Kecmanovic continued to frustrate Sinner deep into the third set, recovering from 3-0 down in the tie-break before receiving a standing ovation after winning three consecutive points to clinch it from 6-5 down.

Sinner, as he has so often done, reset quickly. Despite blood appearing through his white shoes, he proceeded to level the match for a second time with a fourth straight game on his opponent’s serve.

The shock was still on but, as the match moved into its fourth hour, it was Sinner who was able to rally for a final push, reeling off four of the final five games.

After an inconsistent start, he ended the match with 31 aces and 72 winners, and will move on to his next match against Portugal’s Nuno Borges on a positive note after committing only 10 of his 52 unforced errors in the final two sets.