Yeah, the basketball Steve Nash, who played a soccer growing up in Canada and whose brother plays for the Vancouver Whitecaps in USL-1. Some soccer players you may have heard of were there, including Thierry Henry, Saloman Kalou, Jozy Altidore, Claudio Reyna, former Liverpool players Robbie Fowler and Steve McManaman. In addition to Nash representing the NBA, there was Baron Davis, Brazilian Leandro Barbosa (apparently Brazilian basketball players use both of their names instead of just one), Raja Bell and David Lee.
The "pickup game" was a charity event to raise funds for Nash's charitable foundation. ESPN was there and there will probably be a feature story on it sometime soon.
Great photos at the link including one that gives you an idea of being a goalkeeper on the receiving end of a Thierry Henry penalty kick. Not that I wouldn't have minded.