While their personalities may be poles apart, the friendship that Ana Ivanovic and Novak Djokovic forged as juniors over two decades ago remains as strong as ever. Born six months apart in Belgrade, Ivanovic and Djokovic have emerged as the standard bearers for an outstanding generation of Serbian players, with both scaling the top of the rankings and tasting Grand Slam success along the way.
"Novak is a great guy," Ivanovic said. "We've know each other since we were four and he was just starting out in tennis. We shared lot of fun moments, starting at the under 10 and under 12 tournaments we played together in Serbia.
"You would play two or three matches a day, but in between there was nothing to do so you'd play games like hide and seek all the time."
And this appetite for fun and games, for Djokovic at least, is still alive and well in the senior ranks, as Ivanovic found out the hard way at this year's Hopman Cup.
"He's an inspiration to me and for many kids in Serbia as well," Ivanovic said. "But although it's great to see him at the top, it gives him more chances to embarrass and imitate me! I don't know if you noticed in the Hopman Cup, when we played mixed doubles, the Gangnam style song came on and he made me dance. I was so embarrassed. He knew I would be and that's why he did it!"
The pair's ability to look on the bright side of life is all the more admirable considering their childhood growing up in war-torn Belgrade.
"I remember it very well. The very first day it started I was actually on the practice court. They came in and said, 'Look, we heard it's going to start tonight. You better go back home and just stop the practice.'
"The coach was like, 'Yeah, sure, we just finish the basket.' But they're like, 'No, no, no, we go now.'"
NATO's bombing of Belgrade would last for nearly three months, and while it would eventually lead to the withdrawal of Yugoslav troops from Kosovo, it failed to keep Ivanovic off the practice court.
"That was the first day, and then for about a week or two weeks we didn't practice because we didn't know what was going to happen," she said. "After that, we used to wake up early, practice 6 to 8am or 5 to 7am. That was for a couple weeks. After that we went and played tournaments. We tried to live as normal as possible.
"We were not going to school. People were not working. They tried to organize these tournaments. There was a rule that the matches that were on, in case the sirens came on, they had to finish, but no new matches would be called on. They invented their own rules."