Alex de Minaur beats the rain — and fellow Aussie James Duckworth — to advance at Wimbledon, Markéta Vondroušová's title defence lasts just 18 games, while British favourite Andy Murray's withdrawal leaves a doubles farewell at SW19.

Here are the five quick hits from day two at Wimbledon.

1. De Minaur overcomes dogged Duckworth and Wimbledon rain

Alex de Minaur could not be deflected by either rain showers or a determined compatriot as he began his assault on Wimbledon's grass citadel with a straight-sets victory.

James Duckworth provided obdurate opposition but despite forcing a trio of tie-breaks, Australia's number eight could not take a set off the national number one.

With Davis Cup captain Lleyton Hewitt watching on, de Minaur won 7-6 (7/1), 7-6 (7/3), 7-6 (7/4).

A few yards away, on the swathe of outside courts, another Australian also progressed. Alexei Popyrin defeated Thiago Monteiro in four sets in just over two-and-a-half hours.

Adam Walton followed them into the second round with a straight-sets victory over Federico Coria but Alja Tomljanovic went out in the women's event in disappointing fashion to her old rival Jeļena Ostapenko.

While the dogged Duckworth gave de Minaur a useful workout, his resistance would have been frustrating. Combined with the inclement weather, it kept the ninth seed occupied for much of the day.

Beginning at 11am local time (8pm AEST Tuesday), the match did not finish until nearly 4.30pm despite taking barely three hours' play.

One shower arrived just after de Minaur had taken the first set, the second with the third-set tie-break poised at 2-0 to de Minaur.

When they returned, around an hour later, de Minaur sealed victory within five minutes, Duckworth going long on the third match point.

Duckworth had his chances. He broke in all three sets and had served for the second set at 5-4 and the third at 5-3. But both times, de Minaur showed his class to break back.

De Minaur next plays 63-ranked Spaniard Jaume Munar.

Walton's Wimbledon debut began in impressive style, the 25-year-old Queenslander beating the higher-ranked Coria 6-3, 6-3, 7-5 in just over two hours. It was his maiden grand slam victory.

Popyrin had wrapped up his victory just before the second rain break arrived, beating Brazilian Monteiro 6-4, 6-7 (8/10), 6-3, 6-4.

It was Popyrin's second win in Wimbledon's main draw in five visits, the last coming back in 2019. He now moves on to face another South American, Argentina's Tomas Martin Etcheverry.

Tomljanovic followed de Minaur and Duckworth onto Court 12 but those Australian fans who stayed to watch were give little to cheer. The former Aussie number one lost 6-1, 6-2 and there was no sign of the sparks that have featured in past meetings with Ostapenko.

Rinky Hijikata lost in straight sets to Italy's Flavio Cobolli on Court 9, while Olivia Gadecki was beaten 6-4, 6-4 by American Robin Montgomery in 86 minutes on Court 11.

In a late match, Chris O'Connell was swept aside by American number 13 Taylor Fritz, 6-1, 6-2, 6-4, while Thanasi Kokkinakis was trailing Canadian 11th-seed Felix Auger-Aliassime 6-4, 7-5, 6-7 (11/9), 1-1 when bad light stopped play for the day.

2. Markéta Vondroušová's title defence lasts just 18 games

Markéta Vondroušová became the first defending women's champion at Wimbledon to lose in the first round the next year since 1994, eliminated 6-4, 6-2 by Jessica Bouzas Maneiro at Centre Court on Tuesday.

Vondroušová was a surprise title winner at the All England Club 12 months ago, the first unseeded woman to claim the trophy at the grass-court Grand Slam tournament.

Now she enters the books in another — and less-wanted — historic way. The only other time in the sport's Open era, which dates to 1968, that a woman went from a championship at Wimbledon to an immediate exit a year later was when Steffi Graf was defeated by Lori McNeil 30 years ago.

Vondroušová was seeded number six this time, but the left-hander, who also was the runner-up at the 2019 French Open and a silver medallist at the Tokyo Olympics three years ago, was never at her best.

She appeared to still be suffering after-effects from a fall during a tune-up tournament on grass in Berlin last month that hurt her hip.

"This is one of the most important moments in my life, in my career, here in this sport. This is amazing," said Bouzas Maneiro, a 21-year-old from Spain who is ranked 83rd this week, equalling her career high.

"I was like, 'I have no pressure, just enjoy the moment, enjoy the tournament.' Just trying to be free playing, and I did it, so I'm happy for that," she said.

The initial signs of trouble for Vondroušová on Tuesday came right away: She double-faulted three times in the very first game and got broken to trail 1-0.

She would wind up with seven double-faults, part of her total of 28 unforced errors, twice as many as Bouzas Maneiro — who is competing in a Grand Slam tournament for only the third time — in the 66-minute match.

3. Andy Murray pulls out of singles, still set for doubles farewell

Andy Murray withdrew from singles at Wimbledon a little more than a week after surgery to remove a cyst from his spine, and his representatives said on Tuesday the two-time men's champion at the All England Club would make his farewell appearance at the tournament by playing doubles with his brother.

"As you can imagine, he is extremely disappointed," about being unable to compete in singles, his management company said in a statement, adding that Murray "looks forward to competing at Wimbledon for the last time" alongside his older brother, Jamie.

The 37-year-old Murray — who has been planning to retire after the Paris Olympics, which start later this month — was supposed to face Tomáš Macháč at Centre Court on Tuesday in the first round of singles. Murray was replaced in the main draw by David Goffin, who lost during qualifying rounds last week.

Murray won Wimbledon in 2013 and 2016: the first of those made him the first British men's singles champion at the tournament in 77 years, and he was awarded a knighthood by Queen Elizabeth II after the second title.

"Last year, I wasn't planning on it being my last year on the tour. I wanted to come back and play again. Whereas this year, I have no plans to do that. It's coming to the end of my career."

He won the US Open in 2012, made it to number one in the ATP rankings and is the only player to win two consecutive singles gold medals at an Olympics. Those titles came at London in 2012 — when the matches held were at the All England Club — and at Rio de Janeiro in 2016.

A grinding game style, mainly at the baseline, superb serve returning and an unrelenting attitude propelled Murray to success on the court and popularity off it.

In recent years, his career has been marked by a series of injuries, and he had a pair of hip operations in 2018 and 2019, the second of which implanted a metal joint. Murray thought he would need to retire back then but returned to action, even as his mobility was limited and other parts of his body broke down.

"[Wimbledon] is a place that's obviously been really good to me over the years," Murray said on Sunday.

"I'm hoping that, with each day that passes, the likelihood of me being able to play will increase. I mean, it's impossible for me to say, because I also want to go out there and be able to play to a level that I'm happy with," he said.

4: Djokovic's wounded knee no problem in Wimbledon return

For a man who had knee surgery less than four weeks ago, Novak Djokovic looked remarkably mobile in his first competitive match since a meniscus tear forced him out of last month's French Open.

But then, the Serb has long appeared comfortable on Wimbledon's Centre Court, where he has won seven of his 24 grand slam titles.

He was certainly more at home than Czech qualifier Vit Kopřiva, who was blown away 6-1, 6-2, 6-2 in less than two hours.

Djokovic wore a grey support on his right leg for which he had received special permission after promising to try and source a white one.

"I know it's not ideal. I like to go all white and I like to respect the rules," he said.

"I'm very pleased with the way I felt on the court," Djokovic added. "Obviously, coming into this year was different because of the knee, and didn't know how everything would unfold on the court. I'm extremely glad about the way I felt and the way I played.

"I tried to really focus on the game and not think too much about the knee. I've done everything possible in the last three-and-a-half weeks. If it was any other tournament I probably wouldn't have risked it — but I love Wimbledon."

Having dismissed the 123-ranked Kopřiva, Djokovic now plays British wildcard Jacob Fearnley, who was ranked outside the top 500 until he won an ATP Challenger event as a qualifier last month.

5. David Attenborough's colourful impact on Wimbledon and tennis: yellow balls

British naturalist and broadcaster David Attenborough's visit to Wimbledon provided a vivid reminder of his impact on the sport: yellow balls.

With the advent of colour TV and growing interest in tennis in the late 1960s, producers looked for ways to improve the viewing experience.

Tennis balls were historically either black or white.

Attenborough, who worked for the BBC in the '60s when the broadcaster was transitioning to colour, was one of the people who inspired the switch to yellow balls, the All England Club said on Tuesday.

The 98-year-old Attenborough was a guest in the Royal Box at Centre Court on Monday when play started at the grass-court grand slam, drawing applause from the crowd on his arrival. England soccer great David Beckham was alongside him.

The International Tennis Federation introduced yellow balls into the rules of the sport in 1972 "as research had shown these balls to be more visible to television viewers".

Ironically, Wimbledon didn't make the switch until 1986. The official Wimbledon Compendium for that year noted: "Yellow balls were used for the first time, largely as the white balls were getting stained green on the grass, sometimes making them almost impossible to see on TV, where tennis was increasingly popular."