No you cannot.
This is one thing I wish was different, not sure of your intentions but what I do to make the 11 AI a little 'better' is make a few professional a few hard and a few easy. This way since I am not as good as the professional AI I can still race in between the pack and it tends to feel a bit more realistic and seems to make it feel like more racers. Of course if you are much better than the professional AI then this idea will defeat the purpose.