expression
good match for an opponent; worthy rival
Used to express that someone is a worthy opponent or a good match, often in competitive or confrontational contexts. The phrase is somewhat literary and emphatic.
彼なら相手にとって不足はない。
He is a worthy opponent.
あのチームは強いが、我々も相手にとって不足はない。
That team is strong, but we are a good match for them.
A more general phrase meaning 'there is no lack' or 'sufficient', while 相手にとって不足はない specifically refers to being a worthy opponent.
A set phrase combining 相手 (opponent), にとって (for), 不足 (insufficiency), and ない (not). The literal meaning is 'there is no insufficiency regarding the opponent', i.e., the opponent is fully adequate or worthy.