Fade to black, go to another scene or a flash back or something, come back to the resolution. Unless it's a super important fight for the plot or one of the characters involved there's no point going into crazy detail over it, either give a short, barebones, but impactful description or use the scene to develop the character. For things like that, skipping around, using the black holes of the fighting can be interesting narrative tools, and the interpretation of how you skipped around through the character's thoughts the bits of the fight you may get, back story bits, or something else entirely, and then how you get to the conclusion can be fun, because then people can interpret their own meaning of why Jonas' mind went to the memory of being in the zoo with his mother as he fought the giant serpent.

Freud would say he wants to bang his mom. Jung would say he saw an innocence in the ferocity of the beast. Maybe it's juxtaposition? Maybe his mind didn't even go there???

Of course for those fights you DO need to have shown then I say go all out. have 20 pages for a 5 minute fight.