Mathis is a fascinating case to me. On the one hand, the models and metrics all seem to love his bat and he should presumably move quickly through the lower levels if he comes as advertised. On the other hand, I'm curious as to his eventual position. The Cubs announced him as a 3B when they drafted him, but I believe he got most of his playing time at 1B in college. He has the arm and athleticism to be an everyday 3B, but if he needs the reps, he'll likely start at a lower level than Cam Smith so he can work on his development. It also helps that Mathis turned 21 a week ago, so him starting at a lower level wouldn't be the worst thing for him.
Food for thought. We'll see how the next few weeks shake out.