True, but even so, it's very difficult to pitch well when it hurts every time your plant leg lands. I had a minor hip flexor issue for a little while in high school and while I worked through it fine, it was a huge annoyance. Basically, I stretched the hell out of my hip/leg before I pitched to keep it feeling ok. It didn't feel as much painful as it did weak - when I planted, it hurt, but it also sort of felt like my leg just wanted to buckle. Like I said, it was minor, so I never had to sit out and I still pitched well, but if Marcum's is bad, I could see him missing time. Plus, it's the pros, so even if it's not bad, he still might have to miss a start.