What he means is, I'm doing him a favor.
5 seconds sound clip from the Snatch movie soundboard.
You can hear this line at 00:10:55 in the Blu-ray version of the movie.
Quote context
[...]
- What the fuck are you two looking at?
- I hear he's a good fighter, so I'll use him.
- I'll be doing you a favor, boy.
- What he means is, I'm doing him a favor.
- Because everybody knows nobody takes a dive in my fights. Unlike his.
- Here, Errol, I don't think he likes me. You don't like me, do you, boy?
- I do know I can't wait to get out of here. Fuck me, it stinks.
- I like my fights to finish prompt so we can get out before the authorities find out.
[...]