I have a hard time folding the nuts after waiting all day for em. If MP is that good the only hand he has is TJspades but I REALLY doubt it. If there's enough people in the pot some other drawing hands (including sets) could possibly be correct in calling, but you're correct for calling too. There is no way in hell to fold the nut straight. Even if he is freerolling, you still have the other guy' money to split which adds cushioning.