Nalbandian (type of player)
First of all, he has a good first serve. It isnt very good, but he doesnt miss many of them so he's guaranteed to almost always start the rally with him being in the offensive position. He's groundstrokes are soo good that he can go crosscourt or down the line equally well on both wings. He has a good return of service to place him in an offensive position. In almost every rally, with his ability to change the pace and direction of the ball, you are constantly moving.
Secondly, nearly every match he plays goes to a 5 setter. He may be up 2-0 sets and then let you come back with 2 straight sets only for him to win 10-8 in the 5th will dishearten anyone. He seems cranky mentally and you may think the momentum has changed but he usually pulls out the win anyway. The amount he sweats is insane and he always looks like he's about faulter physically but he's still battling it out in the 5th set to win it. He looks out of shape yet he never craps and probably rarely retires in a match. Might I also add that he has insanely good footwork his 'size'. Recently isnt valid because of his injuries. So you are up 2 sets to 0 and he's moaning and groaning, yet some how, 2 hours later, you lose in 5. Hell, you could be out there for 2 hours only to lose 6-3, 6-2.
He hits the ball early off the ground so that you dont have much time to rest, yet he doesnt have that 'kill' shot to consistently hit winners like federer or nadal, therefore, you'll be running even more, thinking you can rally back to win the point.
You put him on defense and what does he do? He either slows the pace down so much that you cant generate your own pace to hit winners or he just lets it go only to make you grind the next point, and subsequently have him win the following point.
He's like Davydenko but with the ability to pull out a tight match. He's kinda like Agassi except he doesnt blow you off the court as much as Andre. And he has the talents of a Federer or Safin to boot.
Oh, did I mention? He also has his drop shot and lob/passing shot to break up the long rallies and make you run vertically, not just horizontally.