What is Michael King’s upside as a starter?

On Tuesday, Michael King tossed four scoreless innings. It was the first time he’d gone four frames in over two years, the latest step in the Yankees’ effort to assess if he can handle a starter’s workload post elbow fracture. King has mostly been solid in relief this season, and he’s seen his velocity jump since the All-Star break (though not quite back to last year’s peak), so it’s safe to say he’s feeling pretty healthy. In red are his per-game sinker velocities, while the blue line represents a smoothed five-game rolling average:

But King’s buildup is seemingly as much about his health as it is about the Yankees’ need to gauge their starting options for next year given the sheer amount of question marks they have in the fold.