Tracy said: "Basically what happened is that I was out with some friends playing around with an ATV that I own and it just got a little out of hand, I flipped it over and it landed on top of me.
"The first three or four days I was making a lot of progress and I thought that I was going to be ok for Mexico. I was doing therapy and some exercises and I think I just overdid it, I just went backwards really fast and the injury got worse.
"I'm very disappointed, but for now the best thing is to relax and let my shoulder heal, I don't want to risk hurting it even more. Dr. Trammell reviewed my X-rays and he recommended that I stay out of the car for a few weeks so the bone can heal properly."
Tracy being ruled out means that his Forsythe Racing team will run their regular two cars instead of the three they had planned to run in Mexico.
Series debutants Buddy Rice and David Martinez will race for the team, with the latter driving Tracy's car instead of the spare chassis that had originally been assigned to him.