Watching tennis can leave any heart pounding. So spare a thought for those often seen chewing their fingernails in the seats allocated to the players' entourage.
Anna and Piotr Wozniacki from Denmark were at Victoria Park last night running the gamut of emotions - as they were 12 months ago when they introduced their daughter to the world.
A then-16-year-old Caroline Wozniacki came to Hong Kong as the tournament's 'ambassador', thinking she'd help out at some clinics and meet a few sponsors, but walked away with the doubles and Silver Group singles crowns filling in for injured players.
It was an impressive start to her senior career and Caroline has spent the past year trying to establish herself in the rough and tumble of the women's pro tour. And more often than not her parents have been there in the stands, watching her every shot.
'You can't worry about injuries,' Anna says. 'You can't even think about them although they happen quite a lot. Watching from the stands this year has been hard because the senior tour is so tough. There are so many players who are so skilled and so good. For Caroline it is a constant learning experience.'
With their daughter ranked 60 in the world, the Wozniackis are hoping the chance to play against some of the world's top players in Hong Kong will lead to bigger and better things.
'The best we can do is just be there for her as she learns,' says Anna. 'I think that is important for any young player. We try not to get nervous but tell her it is OK if she does - she can use that nervousness to focus herself on her game.'