Two-time defending champion Carlos Alcaraz avoided a seismic shock against Italian veteran Fabio Fognini in the Wimbledon first round to set up a meeting with British qualifier Oliver Tarvet.

Alcaraz dug deep to win 7-5 6-7 (5-7) 7-5 2-6 6-1 as he opened the Centre Court play on a sweltering first day of the grass-court Grand Slam tournament.

The 22-year-old Spaniard quickly secured victory when an entertaining contest resumed after a 15-minute pause in the deciding set.

A spectator who had been sitting in the sun was taken ill, with Alcaraz going over with a bottle of cold water to help their recovery.

Alcaraz, who is the second seed behind Italian rival Jannik Sinner, struggled on serve and made uncharacteristic errors off the ground throughout a four-and-a-half hour contest in temperatures topping 32C.

In his final Wimbledon appearance before his planned retirement, 38-year-old Fognini twice fought back to force the decider but Alcaraz regained control to extend his winning streak to 19 matches.

Alcaraz claimed his fifth Grand Slam title at the French Open earlier this month - beating Sinner in an all-time classic final - before lifting the Queen's trophy on his return to the British grass.

Alcaraz roared in relief when he finally ended Fognini's resistance, breaking into a broad smile and sharing a friendly embrace with his opponent.

"I tried my best but I can be better. I need to improve in the next round," said Alcaraz.

Next he will face 21-year-old Tarvet, who gets a shot at one of sport's superstars after beating Switzerland's Leandro Riedi on his Wimbledon debut.

Nightmare start for Alcaraz

Coming from the sun-drenched region of Murcia, Alcaraz is well accustomed to playing in searing heat.

Nevertheless, having to start his latest title defence with a lengthy contest in the tricky conditions was far from ideal.

The players expecting to go deep over the fortnight want to preserve as much energy as possible in the earlier rounds, but Alcaraz needed to dig deep into his physical and mental reserves to see off Fognini.

"Playing in such a high heat is really difficult to deal with and it is even tougher when you're playing long matches, long rallies," Alcaraz said.

"Part of the match you can feel down a little bit because of the sun hitting all the time. I have to be ready to battle."

Alcaraz is used to playing the opening match of Wimbledon on its most iconic court - as tradition dictates the reigning men's champion does - but lacked the freedom and fluency for which he is known.

On a buzzing Centre Court where the atmosphere rarely faded despite the stifling weather, Alcaraz lost serve five times in an absorbing contest between two of the sport's finest entertainers.

Alcaraz has tinkered with his opening shot this season and that may have been a contributing factor to a first-serve percentage below 50% which allowed Fognini to constantly apply pressure.

Fognini turned professional when Alcaraz was still a toddler but the expressive Italian showed how he stills loves to show off his skills on the grandest stages.

Returning smartly and playing with his trademark variety befuddled Alcaraz, whose frustration was shown in his gesturing and chuntering towards his team.

But when Alcaraz is hitting freely, it spells troubles for his opponents.

A light-hearted exchange at the start of the decider - when Fognini playfully threatened to hit a ball at his younger rival - brought the smile back to Alcaraz's face.

From that point, he found more rhythm and cruised through the fifth set, either side of the enforced emergency break which disrupted Fognini's focus.

"Playing the first match on Centre Court is never easy," said Alcaraz.

"I've been practising really well and playing really well but Wimbledon is different. I could feel the difference."

Fognini waves goodbye to Wimbledon

Fognini is a colourful character who can be a joy to watch but has also been known to overstep the mark – notably in a 2019 outburst when he said he wished a bomb would explode on Wimbledon.

The manner in which he pushed Alcaraz, though, was a reminder of the fluid, natural talent which has regularly troubled the very best players over the years.

The former world number nine is one of the few players to have earned multiple wins over Rafael Nadal on clay, while his ability on the red dirt also troubled Britain's Andy Murray.

Fognini, whose best run at a major came in a run to the 2011 French Open quarter-finals, has announced he planned to retire at the end of this year, although he has not specifically said when.

After sealing victory, Alcaraz quickly directed the crowd to applaud Fognini and he was given a heartfelt ovation before flinging his shoes into the crowd.

"I don't know why this is his last Wimbledon because with the level he is playing he can play for another three or four years," said Alcaraz.

"Fabio is a great player and has shown his level and talent throughout his career.

"I'm sad it's probably his last Wimbledon but I'm happy to have shared the court with him."