The bond between an athlete and a coach can sometimes be incredibly strong!
But for Serena Williams, the line between coach and a little somethin' on the side got a little bit blurry when she decided to do a little flirting with her hitting partner Sascha Bajin!
"You have big, big lips. They belong on a black guy. That's why I love black guys. They have nice lips."
And if that wasn't enough to get Sascha blushing, she decided to sit on his lap and called him "big daddy!"
But before you start getting excited about a budding romance, Serena laughed the whole thing off and says that she would NEVER date her hitting partner, which is a shame because he's pretty darn good looking!
Ch-ch-check out Serena's flirty side (above)!