Alex's service action is modelled on Goran Ivanisevic who was one of Alex's tennis idols
Alex has quite a low ball toss which makes it serve difficult to read. This and the very fast action he has, makes the ball skid off the court with quite a low bounce which is why his serve is most effective on grass and indoors. The only problem he can have at times is that his serve depends a lot on him being in a rhythm with it [this is because of the low ball toss and the action], if not the 1st serve percentage does tend to fall quite low.