Actually it is easy to deny. It is a myth started by the Nadal hating brigade. David Ferrer is Spanish and he has beaten Nadal 4 times including twice in slams. Moya has beaten Nadal multiple times, and pushed him on other occasions even aging and past his prime. It just so happens Ferrer and Moya are the only Spanish players good enough to compete with Nadal. People who think the likes of Clowndasco, Lopez, Almagro, Robredo, are good enough to regularly challenge Nadal if they simply wanted to are delusional. If you arent good enough to be regularly ranked in the top 10 or are a fluke excuse of a top 10 player (aka Verdasco) you shouldnt be able to beat someone like Nadal hardly ever, if at all. All the same Spanish guys who have never beaten Nadal have never beaten Federer too, and in fact some who have (eg- Ferrer). That group are doing as well vs Nadal as they ought to given their ability levels