A character in my game is stuck mid-animation when the game's not running. Why? Could that be screwing up its limb positions?

This is basically two questions, and possibly only one of them is a big deal. But yeah, my player character was imported in Semi-T-pose, but at some point in the development process, the Unity editor decided to display him in the process of an attack animation. This doesn’t happen with NPCs in the same scene; they are in their imported poses when the game is not running. I’d like to know what is causing this, but also if it in turn affects the way my player character animates when the game is running, because yeah, there are some iffy bits. While the game runs, his right hand bends upward in kind of a 90 degree angle, while his left one is held rather normally, and punch animations don’t really go out to his front.

So any help with all of this would be appreciated; hopefully it’s easily explained.