We're in a grand ball room in a central London hotel, but few of the hundreds of people packed in here are gazing at the finery on the walls and ceiling. Any outside light has been completely blacked out, yet more people are wearing sunglasses indoors - in one brazen case, mirrored - than I've seen since the New Romantic age. What IS going on?
Well, it's the setting for the PokerStars.com European Poker Tour London event, and the person to explain its appeal for these players subscribing in their droves (entry fee £5,000 buy-in, total prize pool £3,351,350) is sitting at one of the tables, generously dispensing advice to newcomers at the exhibition tournament before the serious business starts the following day.
His celebrated sunlit straw thatch is tucked away under a baseball cap, but when he eventually stands up, his build has the giveaway of a sportsman. This whole setting - the bustle of tables, the click-click of chips, the dealing of cards by scarily young dealers - may be a world away from the gentle thwock-thwack-clap of Wimbledon but, later in conversation, Boris Becker assures me many of the same skills are required.
"Mentally, it requires very much a similar approach in terms of discipline, endurance and concentration. The mind-reading of others has to be at its best," he explains. "Poker is actually a very slow game, which requires patience - just as when you win a Grand Slam, it takes two weeks and years of preparation, not just one good ace, but seven good matches. Similarly, it takes five excellent days of poker to win a tournament."
This is not uninformed musing. Becker has been a poker player since 2008, nearly a decade after retiring from professional tennis, and is now an ambassador for PokersStars.com, playing between five and six tournaments a year (of around five days each) around the world.
He calls himself "a passionate amateur", but admits he's also "got into the money a few times, often enough to keep the fire burning".
Bless him, even as he says this, the Boom Boom who ignited Wimbledon with his teenage energy and enthusiasm (Becker remains Wimbledon's youngest ever men's champion at 17) is still much visible, and it is clear those days aren't far away in his mind:
"The poker circuit reminds me of the days when I was 25 years old and travelling the world with a tennis racquet - the players, hotels, but also the game itself. It has a great, competitive edge, when you need to be on top of your game all the time, and that reminds me a lot of tennis."
Becker is by no means the only supreme sportsman to have transferred this competitive spirit onto the poker table - which other tennis players does he think would have been good poker players?
"I'm convinced Roger Federer would make a good poker player, because he has a god-given talent to play tennis and he's very humble and casual," muses Becker. "I'd love to have John McEnroe on the poker table, for the excitement and the noise. Agassi and Sampras are both good players, I know."
Poker may lie somewhere between chess, bridge and darts on the sport/game/hobby spectrum, but as with every other competition in these increasingly lucrative days, the players take their physical fitness very seriously. There is not much alcohol being served here tonight - as Becker puts it: "This is a game that provides competition for old and young, fat and skinny, it's the competition that drives it. But in the healthy body is the healthy mind, easier living is just a better way of spending your days."
Finally, if once again, Becker's singular sense of competition means that he is working for his supper (which he has been doing since he was 15 years old) is there any sport which allows him to be free of the pressure of sponsorship and winning? He's quick with a humble, non-competitive reply:
"Golf. Believe me, nobody is sponsoring me to play golf."
Becker has a handicap of seven. I guess it's all relative.
The PokerStars.com European Poker Tour (EPT) is Europe's richest and most popular poker tour. In it's eight-year history, almost 40,000 players have hit the felt, and the EPT has paid out over £200 million in prize money. The EPT London event was won this year by 26-year-old German Benny Spindler, who walked away with the top prize of £750,000. Previous winners include writer, broadcaster and Team PokerStars Pro Vicky Coren. The next stop on the European Poker Tour is in the Greek coastal resort of Loutraki, where the buy-in is €4,000.