Because Kryptonians have a limit set by the armor they wear because they become incapacitated when it breaks. Well, the facemask specifically
And seeing as I would rate thors face far more durable than that mask and Kurse messed it up pretty easily. It stands to reason he could do so here.
Namek ttries to blitz he gets the mjolnir treatment. Backhanded slapped to the side. Rinse. Repeat till forum win.
What do you mean slugfest only. What else can either of em do besides slugging it out?