When Wimbledon ended last year, there were two great takeaways from the tournament: Novak Djokovic would soon be pulling away in the grand slam title race and Ash Barty was beginning a new era of dominance.

Both seemed to be knock-ins, and yet neither has come to pass. Djokovic missed out on a calendar Grand Slam in New York before being banished from Australia, and despite drawing level with Rafael Nadal and Roger Federer on 20 grand slams with his Centre Court triumph, he now finds himself two adrift of the Spaniard again.

Barty, meanwhile, has left her own party. The then world number one stunned the tennis world by retiring in March, having added the Australian Open she so craved to her trophy cabinet.

Djokovic and Iga Swiatek head into Wimbledon, which begins on Monday, as the top seeds.

Stats Perform has used Opta facts to consider what the men's and women's singles might deliver.

KING ROGER'S REIGN IS OVER, BUT DJOKOVIC AND NADAL KEEP GOING STRONG

There will come a time when the Wimbledon favourite is not one of the 'Big Three'. That time is not now.

Djokovic is the man most likely, as he targets his fourth straight Wimbledon title and seventh overall; since 2011, when he beat Nadal in the final, the Serbian has only been absent from the trophy match three times (in 2012, 2016 and 2017).

His winning run of 21 matches at Wimbledon is the fifth-longest in the men's singles. Bjorn Borg holds the record (41 between 1976 and 1981).

The last player other than Djokovic, Nadal, Federer and Andy Murray to win the Wimbledon men's title was Lleyton Hewitt in 2002. Federer is absent this year and may have played his last Wimbledon.

Nadal has won Wimbledon twice, in 2008 and 2010. He won the French Open, Wimbledon and the US Open in 2010, the only season of his career when he has won three slams. This year, at the age of 36, he has the Australian and French Open trophies already locked away, potentially halfway to a calendar Grand Slam, last achieved in men's singles in 1969 by Rod Laver.

Should Nadal pull off another major coup, it would make him only the second man in the Open Era (from 1968) to win the season's first three singles slams, after Laver in 1969 and Djokovic last year.

Can the rest hope to compete?

What of Murray? Well, only Federer (19), Sampras (10), Laver and Jimmy Connors (both nine) have won more ATP titles on grass than the Scot in the Open Era. If he recovers from an abdominal strain, he has a shot at reaching the second week. He will of course have the full backing of the Wimbledon crowd.

Last year's runner-up Matteo Berrettini is fancied more than Nadal by many, having won Stuttgart and Queen's Club titles in the build-up.

There has not been an American men's singles champion since 2000, and although the United States has six players seeded, more than any other nation, it seems a safe enough assumption we will be saying a similar thing again in 12 months' time.

Third seed Casper Ruud has never won a singles match at Wimbledon, while fourth seed Stefanos Tsitsipas has not had a win since reaching the fourth round in 2018. Daniil Medvedev, the world number one, cannot compete at The All England Club after their contentious decision to ban Russian and Belarusian players due to Russia's invasion of Ukraine.

IF SERENA CAN'T CHALLENGE SWIATEK, WHO CAN?

From the jaws of retirement, Serena Williams is back. Silence from the 40-year-old about her intentions had become almost deafening, and yet here she is, back at Wimbledon on a wildcard, hoping to rekindle the old magic.

Because she has pushed back against the doubters for over two decades now, you have to take this seriously. Her haul of 23 grand slams is one short of Margaret Court's all-time record and Williams would dearly love to at least match it.

Three years ago, Williams became the oldest player to reach Wimbledon's women's singles final when she lost to Simona Halep. Six years ago, she was the oldest champion when she beat Angelique Kerber.

Only four women in the draw this year besides Williams have been champion before: Petra Kvitova (in 2011 and 2014), Garbine Muguruza (in 2017), Kerber (in 2018) and Halep (in 2019).

World number one Iga Swiatek starts as favourite. Junior Wimbledon champion four years ago, she has scooped two women's French Open titles since then and is on a 35-match winning streak.

After triumphing at Roland Garros in early June, Swiatek will hope to become the first woman since Kerber in 2016 (Australian Open and US Open) to win two singles slams in the same season.

The only competitive warm-up for Williams came in two doubles matches at Eastbourne, having not played since sustaining a hamstring injury at Wimbledon last year. The seven-time champion might consider it a challenge that there has never been an unseeded Wimbledon women's singles finalist during the Open Era.

The women's top two seeds have not met in the final since Serena faced her sister Venus in the 2002 title match, so don't hold your breath for a Swiatek versus Anett Kontaveit showpiece on July 9.

Could Gauff be best of the rest?

Coco Gauff made a breakthrough with her run to the French Open final. Although she was blown away by Swiatek, for the 18-year-old American it was another mark of progress. Gauff reached the fourth round in Wimbledon in 2019 (lost to Halep) and 2021 (lost to Kerber).

Fitness is likely to be the key factor in how US Open champion Emma Raducanu fares at her home grand slam, given her injury problems. Raducanu reached the fourth round on a wildcard last year and the 19-year-old will attempt to become the first British woman to reach that stage in back-to-back seasons since Jo Durie (1984, 1985).

Ons Jabeur, meanwhile, should not be discounted. The world number three reached the quarter-finals at SW19 last year and heads to Wimbledon having won on grass at the Berlin Open, albeit Belinda Bencic had retired hurt in the final.

The likes of Gauff, Raducanu and 21-year-old Swiatek will attempt to become the youngest woman to lift the trophy since 17-year-old Maria Sharapova triumphed in 2004.

A first-round exit for Swiatek would leave the event wide open, but don't count on it. In the Open Era, only three times has the top-seeded woman lost in round one: Steffi Graf in 1994 and Martina Hingis in 1999 and 2001.