When I raced (running) in college, I never thought of who was behind me. My thoughts always were along the lines of "go go go go go, up the hill, pick it up around the bend to lose anybody." I thought of how I could run faster, yet relax. I thought of what I was going to do next. How much further I had to go in the race. Whether or not I could keep my current pace up, when I should start my kick.

Focus on your riding. Hit the apex of the next turn perfectly. Accelerate out of the turn, be in the right gear when you need it. Never think of what's behind you, only think of how you can ride better and finish faster.