What does the phrasal verb "hold up" mean in this context?

Question

This context is from the movie "on The Waterfront" The people speaking talk about a boxing mach in which one was a contestant and the other a spectator in the audience.

person 1. Man, he really dumped you.
person 2. He dumped me?
person 2. What would you say if I told you I held that bum up for half a round?
person 1. I could see he was hurt.
person 2. What did you think I was doing with them combinations, petting him?

TFD definitions for the phrasal verb "hold up"
2. verb To physically keep someone or something upright. In this usage, a noun or pronoun can be used between "hold" and "up."
He was so sick that I practically had to hold him up in the pharmacy line.
3. verb To delay or slow someone or something down. In this usage, a noun or pronoun can be used between "hold" and "up."

But these definitions don't make much sense because further converstation indicates that he lost that fight on purpouse because "he was doing a favour to couple of palls of his" also he brags about having his opponent "figured out" and that if it wasn't for the favour he would've won.

Answer 1

It's hard to tell since there's so much idiomatic usage here (for instance, it seems that "dumped" means "beat badly," but I'm unfamiliar with that usage). However, I think your definition #3 applies: The speaker is saying that he kept his opponent from winning for half a round; in this sense he "held up" his opponent's victory, delaying him from winning. (This makes all the more sense if he "threw the match," losing on purpose. This is often done to benefit people who have bet on the outcome, often betting on exactly when the match will be won.)

Answer 2

I think definition 2 is the correct one here. When the spectator says "he really dumped you", the boxer reacts angrily. The natural interpretation for me is that the boxer is saying "He didn't 'really dump me', I almost had to carry him for half a round just so he didn't fall down."

The comments about "he was hurt" and "what did you think I was doing with them combinations?" suggest that Wilson was not dominating the fight, but "I delayed his victory by half a round" doesn't seem like something the boxer would say so angrily, because it is not something to be particularly proud of or something that contradicts the original statement about losing the fight badly.