Originally Posted by Tannhauser
In my opinion, you should usually do first the exercise which (a) requires more coordination and (b) activates the greater amount of muscle mass.
As squats fulfil both of those criteria, If I were you, I would do squats first.
Just from a safety point of view, I've never liked the idea of squatting with pre-exhausted thighs - I think it's a recipe for disaster. Leg press is a much more controllable exercise that doesn't require any element of balance.
This all makes a lot of sense.