Doubles delight

Doubles delight

As these photographs show, Ana and Andrea Petkovic added extra intrigue to their doubles matches in Miami this week: the pair would reward each other financially for certain achievements such as aces and winners, exchanging money mid-match.

Petkovic explained, with a hint of sarcasm: "I won 20 bucks. Ana, I think she shed one tear, because I hit aces. I usually go more for percentage and trying to mix it up. Yesterday, like in the first or second game I hit three aces, which is 15 bucks already.

"Also on the decisive point I hit a return winner, which is also 5 bucks, so 20 bucks all in all. She earned - I think she had one ace and one important volley, so that was $7. So $13...You have to pay in the changeovers."

The duo first competed together in Stuttgart last year, but didn't win a match until this week's Sony Ericsson Open. They proved a hit with fans in Miami, not least thanks to the "Petko dance" they performed immediately following their two victories in Key Biscayne.