Carlos Alcaraz will be the main attraction on the opening day of Wimbledon as the Spaniard begins his quest to retain the title while later in the day world number one Jannik Sinner will look to put down an early marker in his opening match.

Alcaraz, 21, beat Novak Djokovic to the title a year ago and has since taken his Grand Slam haul to three after winning the French Open earlier this month and despite being seeded three will be favourite to rack up number four.

He will open Centre Court action against Estonian qualifier Mark Lajal in the first of what he hopes will be seven matches to become only the fourth player in the professional era to win four Slams at age 21 or under.

World number 269 Lajal, who is one week younger than Alcaraz, is bidding to become the third man in history to defeat the defending champion in the first round at Wimbledon.

"Obviously I want to put my name on that short list to win Roland Garros and Wimbledon in the same year," Alcaraz, who could join Rafa Nadal, Roger Federer and Djokovic by achieving that feat, told reporters.

"I know that it's going to be a really difficult and big challenge for me, but I think I'm ready to do it."

Italy's Sinner, who won this year's Australian Open and knocked Novak Djokovic off the top of the rankings, faces a vastly more experienced opponent in Germany's Yannick Hanfmann.

There will be home interest on Centre Court's opening day schedule with Emma Raducanu returning after missing out last year because of injury.

The 2021 U.S. Open champion, who required a wildcard as she works her way back up the rankings, faces a tough test against Russian 22nd seed Ekaterina Alexandrova.

"For me, I feel like it's just a great opportunity to try to get a good scalp, try to enjoy playing how I have been in the last few weeks, and just get back into it," Raducanu said.

Coco Gauff, enjoying a strong season, concludes Centre Court action on the opening day as the women's second seed takes on fellow American Caroline Dolehide while on Court One, Aryna Sabalenka, the third seed and many people's favourite for the title, opens against American Emina Bektas.

"I think everybody has an equal shot and it's just about who can perform better that week," Gauff said.

Russian Daniil Medvedev is first on Court One with Sinner book-ending the day on the second-biggest court.

Fans flooding in to the All England Club, many having camped out overnight, will be spoilt for choice with big names in action across the outside courts with Norway's eighth seed Casper Ruud, who has more wins than any player on the ATP Tour this year, up against Australian Alex Bolt.