l'avversario in English:

He surprised his opponent.

The manager balanced the strength of his team against that of their opponent and sighed.

The talented young chess player is very bold. He deliberately lays himself open to attack, makes himself vulnerable and then checkmates his opponent when least expected.

Iaido is a form of swordsmanship in which one strikes down an attacking opponent with one blow of the sword quickly drawn out of its sheath, whether the practitioner is sitting or walking.

Off-target. My opponent hadn't been hit.

He resolutely pushed forward from the start, overwhelming and pushing out his off-balance opponent.

Think of your opponent as nothing more than a handful of ash.

Everything was allowed: You could kick, trip, hit, or bite your opponent.

I don't think she's an opponent you can ignore like that ... "That's right, they say a cornered rat bites back, don't they?"

The atheist completely flummoxed her opponent in the debate by asking, "And who created God?"

This isn't my blood. It's all splash-back from my opponent. There isn't a single scratch on me.

Susanne Lenglen shocked the spectators by beating her opponents and winning several major titles.

My opponent was really good, that's why I lost.

Our opponents were too good for our team to beat and we lost the match 3–1.

opponent = adversary = enemy