Coria was in his prime in 2005. It wouldn't have mattered even if the rest were in the primes. The fact is that they are Roland Garros champions and made up for a better opposition than all the Rookie chumps Federer played in grandslams until 2007.
You obviously didn't watch tennis then, because what I'm trying to say is that they cannot be considered rivals having never faced Nadal at Roland Garros and even when any of these players did face them, they were out of their primes. The only one Nadal faced at Roland Garros was Moya and that was in 2007 when Moya was almost 31 years old.
And no, Coria was struggling with injury as early from January when he was having leg problems, then his serve started to show minor signs of deterioration and it was obvious that his confidence had dropped significantly.
Here's another way to put it, despite Nadal never facing any barring Moya at Roland Garros. Here's the last time Nadal met the following: Coria - 2006 Monte Carlo. Gaudio - 2006 Monte Carlo. Corretja - 2003 before Roland Garros. Moya - 2008 Hamburg. Ferrero - 2010 Monte Carlo. Costa - 2003 Monte Carlo.
So his longest term 'rival' from this group was Ferrero, of whom he faced first 2 years out of Ferrero's prime and last at the age of 23.