Watch as Kevin Anderson sings happy birthday to his wife, Kelsey, with a little help from the crowd at The O2 in London. 'I think from today's match, I did a really good job of not giving him time. I think just overall I've done that pretty well against him. I think that's why he's been such an amazing clay court player because he creates a little bit more time. When he has time, he's just so dangerous', the South African said. 'So I think, you know, I've had to play great tennis against him. I think I've done a great job of just making him feel a little bit uncomfortable. That's why I've had good success against him so far.'