So far, in the Gold Cup, Aldo de Nigris has been an absolutely lethal weapon off the bench. In Mexico's friendlies leading up to the competition, with 'Chicharito' Javier Hernandez unavailable, de Nigris started and played relatively poorly. I'm sure you've already figured out where this is going.
Because of Humberto Suazo's lack of availability over the last two seasons for various reasons (international duty, injuries, loan to Zaragoza), Aldo de Nigris has established himself as a regular starter for Monterrey, and he's been a good one. He averages a goal every other game for the Rayados - a great strike rate - and his size relative to the average sized player in the Mexican Primera makes him a significant weapon.
However, along with that size, de Nigris also has pace, power, and a high work rate. He is more than a target striker, he's a very good all-around athlete. When he comes off the bench against tiring teams, those positive attributes are even more apparent.
You have to wonder whether or not Victor Manuel Vucetich is watching El Tri at the Gold Cup, wondering if he should use de Nigris in the same way. It would make sense, especially with the personnel he has. With Suazo, Neri Cardozo, Osvaldo Martinez, Walter Ayovi, Luis Ernesto Perez, and Jesus Zavala in the team, he's not necessarily losing anything in talent by leaving de Nigris on his bench to start the game.
Monterrey are a team loaded with players who can play multiple roles and who are very technically and tactically adept. They're excellent at keeping the ball, just as they are excellent on the break. They're a very good and more importantly, a very dynamic team.
Would Monterrey be better served by leaving one of de Nigris or Suazo on the bench in most matches, then bringing them in for a midfielder after the opposition has gotten tired as a result of chasing the ball for 45-60 minutes? It seems silly at first thought to leave one of them on the bench, but it might be in Monterrey's best interests. Just some food for thought.