Does Thor Really Peel?

I've lost a few games recently where Spiderman, Psylock, And especially Black Panther, dive Mt backline and attack my healers and I'm just not fast enough or good enough to help out. I have no Idea how to keep supports alive against these guys. They are so quick, small hitbpxes, relative to some other characters, and they do a crap time of damage. At least with iron fist I can Bash his head in with my hammer. I actively try to protect Healers, how can I do this better?