Jake Arrieta is a power pitcher with a full arsenal that consists of six pitches, but really he sits with a basic four. He will live and breathe off the powerful fastball, his aggressive nature, and round it out with sharp breaking pitches. His effort sometimes reaches more than you want to see out of a starter, but it's something I feel will decrease with age and experience. I still rate him as a “thrower” rather than “pitcher” until he completely learns the craft. I have first hand sources that suggest he is eager to learn from others and one day he can become a top of the rotation arm with a few minor changes to his overall makeup.