Dimitrov was serving for the second set, but got broken. Then he had four set points on Nadal's serve, but Nadal holds for 5-5.
I'm not watching but this feels a bit like the Fed-Nadal matches of old. Roger would have chances, but be unable to take them, and in the end it all would go Rafa's way.
Let's see whether it turns out like this here. At least Dimitrov doesn't get broken himself, holding to 30 to make it 6-5 and force Nadal to serve to stay in the set once more.