He has yet to beat Nadal in a big match.
Never beaten him in a Slam, lost both finals they played, and lost the Olympic semi.
Nadal and Novak never played in a hardcourt GS, of course Rafa will always win on clay. He's just unbeatable on dirt, but what makes for instance IW semi or Canada masters semi less important that Queens final?
Novak had good and very important wins over Rafa, but Rafa won the most important matches, that's for sure. I would actually put Olympics semi the biggest Rafael's win over Novak