He seems to lose control of the breaking ball, and then everything crumbles. It seems like every single time he hits a LHH with the curve the inning turns into a disaster.
He’s also interesting in the sense that his 4 seamer has bad shape with only 7” of rise. That’s right in the “hit me a mile” range of fastball movement.
So I wonder if the curve and mediocre 4 seamer are an effective pair, and if the curve isn’t working the 4 seamer is bad without the complimentary pitch.
Personally, I think Morton should be throwing the sinker much more than he does. It’s a better pitch by itself, and may be able to stand on its own better when the curve isn’t working.