Great talent. Many similar topics to this, but I remember someone writing a great post about Nalby went something like this -
Look at the guy. He has no really special physical attributes. He's not the greatest mover or the quickest, or best defender. He can't just fall back on defending all day, getting balls back. He isn't the strongest or most powerful. He isn't tall. He has a weak serve.
And yet despite that, the guy has the ability to beat and cause trouble to most anyone including some of the best in the game. For me, that's a great sign of talent. He has to primarily rely on his point construction, and shotmaking ability to get by. He can't fall back on the crazy defending/flexibility/physicality of guys like Nadal, Djoko and Murray. He doesn't have the tremendous serve of a Fed. He doesn't have the easy power of a Del Potro.
It's tough to play consistently when you don't have much else to rely on.
Is this the post you're talking about?
Nalbandian is respected because he's an elite tennis player without a serve or any athletic ability. All he has to go on is hand eye coordination and court sense.
I remember watching him hold match points against Nadal at Indian Wells last year, a guy about 20 lbs overweight against the fittest player on tour, predicting every one of Nadal's shots and always staying in control with precise deep balls, all while being hampered with a hip injury and hitting 80mph serves.
They love him not because he's the best, but because he makes normal people want to play tennis.
There are players with bigger serves and better movement, but no one hits a better ball than Nalbandian.
The fact is, there are players more talented than Nalbandian, the definition of talent being the capacity to be successful at what you do. It's just that humans are more appreciative of hand eye coordination and court sense(Nalbandian) than a good throwing arm and self discipline(Roddick), even though the latter will win you more titles. People watch tennis to be entertained, so it's only natural that they would throw praise at Nalbandian and disregard Roddick.