"For me sometimes, I like the restrictions... you don't have to hobnob with people, with crowds. It's just a quiet life," O'Sullivan told AFP at a Wednesday press conference.

The seven-time world champion, along with five top international players, landed in the Chinese finance hub for the four-day Hong Kong Masters, which begins Thursday.

Hong Kong has begun relaxing some of its pandemic restrictions, which followed a looser version of China's zero-Covid strategy but were still among the strictest in the world.

The city scrapped its unpopular mandatory hotel quarantine last month, but visitors are barred from restaurants and bars for the first three days after arrival.

Departing from his usual irreverent tone, O'Sullivan said he "respected" the rules and even managed to find a silver lining, saying they eliminated distractions.

"When you play sport, you just want to be left alone in the quiet and allowed to play your game."

But local snooker star Marco Fu posted on Facebook that he spent the better part of an hour teaching the world's top players how to use Hong Kong's contact tracing app, which is mandatory for entering restaurants and bars and many public venues.

Four-time world champion John Higgins said the need to wear face masks in Hong Kong brought back bad memories of pandemic-era life in Britain.

"It's just something you have to put up with," Higgins said. "Hopefully life (in Hong Kong) can become a little bit less stressful."

The tournament is marking its return after a five-year absence, and organizers are eager to bill it as Hong Kong's first major international sports event since the pandemic began.

Vincent Law, who chairs the Hong Kong Billiard Sports Control Council, said the event benefited from the scrapping of hotel quarantine even though the policy U-turn left organizers scrambling.

The visiting players received a partial exemption from Hong Kong's latest Covid rules, which allowed them to practice and compete in the tournament venue.

Matches will be held in the cavernous Hong Kong Coliseum, which may draw a record-beating crowd of up to 9,000 spectators as 90 percent of tickets have been sold, Law said.

The competition will also feature Judd Trump, Mark Selby, Neil Robertson, Zhao Xintong and Hong Kong player Ng On-yee, the three-time women's world champion.

While Hong Kong is gradually reopening, top players said mainland China -- which used to be a big chunk of snooker's competitive calendar -- remained a no-go.

"I don't think it can be financially viable for (players) to do the seven-day quarantine before the tournament even starts, because we don't have that amount of room in the calendar," Selby told AFP.

"If the quarantine is reduced to like what the quarantine is here in Hong Kong, I think tournaments can go ahead in China."