'Infinite strength' has weird limits in fiction, but can usually be troped in three big, easy ways. The first is to threaten something that character cares deeply about. He may be invincible, but his world is not.

The other is to have them at limited potentials of that power, or limit them by their incompetence or inexperience. This is the Matthew Malloy or Scarlet Witch situation, they had/have power but are sometimes written with zero control of that power.

The last and easiest, is to use abilities that do not depend on strength. Strength is always troped by magic and telepathic users of at least some skill. Can't kill what you're fighting? Teleport it to hell! Trick its mind into fighting someone else. Trick it into thinking there's nothing wrong, or Charles Xavier's method, 'you sleep now'.

Though there are sometimes limits to that. See - The Hulk.

"He's too angry! His mind is madness!"

No idea why they never think of just levitating him. He can't smash if he can't get to the ground.