The truncated 2020 tennis season came to an end on Sunday when Daniil Medvedev defeated Dominic Thiem in the championship match of the ATP Finals in London.

AFP Sport looks at five things to remember from the coronavirus-impacted year:

Djokovic’s rollercoaster

Novak Djokovic started the year with an eighth Australian Open and 17th Grand Slam title and finished it by equalling Pete Sampras’s record as a year-end World No. 1 for a sixth time.

In between, however, the darker side of the 33-year-old emerged.

While the sport went into coronavirus lockdown, the Serb launched his ill-fated Adria Tour in June.

With no social distancing and with players pictured dancing shirtless at a packed nightclub, Djokovic became one of a number of players to test positive for coronavirus.

Grigor Dimitrov, Borna Coric and Viktor Troicki also became ill and the project was abandoned.

"You can’t be dancing on tables, money-grabbing your way around Europe or trying to make a quick buck hosting the next exhibition. That’s just so selfish,” said Australian firebrand Nick Kyrgios.

Djokovic then saw his hopes of an 18th Slam end with a disqualification from the US Open after inadvertently hitting a line judge with a ball.

His hopes of becoming the first man in half a century to win all four Slams twice ended in a straight sets defeat to Rafael Nadal in the French Open final.

Nadal’s 13th 

Roland Garros

Rafael Nadal had skipped the US Open, where he was defending champion, due to fears over the escalating health crisis in New York.

The decision paid off as he swept to a 13th Roland Garros and 20th career Grand Slam title in Paris in October.

The French Open had been pushed back four months due to the pandemic and Nadal had entered the tournament fearing the heavier balls and autumn conditions would conspire against him.

He need not have worried as he reached the 100-win mark at the tournament without dropping a set, making light of the 1,000 fans a day limit.

The absent Roger Federer, also a 20-time major winner, hailed it as "one of sport’s greatest achievements”.

Game, set, match

The global pandemic closed down tennis from March until August.

Wimbledon was cancelled for the first time since World War II while Roland Garros was moved from its traditional May/June slot to September/October.

The Davis Cup and Fed Cup finals were binned as were the ATP and WTA end-of-season Asian swings.

Most events were played behind closed doors. Players racquet-tapped instead of shaking hands and were told to fetch their own towels.

Kenin and Swiatek give Slams new look

Serena Williams’ quest for a record-equalling 24th Slam goes on after another season of frustration at the Slams.

The 39-year-old lost in the third round in Australia, semifinals of the US Open and pulled out injured after the first round of the French Open.

With No. 1 Ashleigh Barty not playing at all after the resumption, something of a power vacuum emerged.

Sofia Kenin had already claimed a maiden Slam at the Australian Open while Naomi Osaka claimed a second US Open and third career major in New York.

Kenin’s hopes of a second Slam in 2020 were undone by charismatic Iga Swiatek of Poland who won a shock French Open.

The 19-year-old, at 54, was the lowest-ranked woman to capture the Roland Garros title in the modern era and was Poland’s first ever major champion.

Freeze — you’re No. 1

The chaos caused to tennis by the pandemic saw the governing bodies freeze world rankings from March, allowing points to extend beyond the traditional 52-week window.

Barty remained World No. 1 despite playing just three events — winning the Adelaide tournament followed by semifinal runs at the Australian Open and Qatar Open.

Former US Open winner Bianca Andreescu didn’t play a single match in 2020 after injuring her knee at the WTA Finals in Shenzhen in October last year.

The Canadian will still finish at seven in the rankings.

Roger Federer will end 2020 ranked at five following a season where he only played the Australian Open before undergoing knee surgery.