- What's a southpaw?
- A southpaw means you're left-handed. And a southpaw throws your timing off, you see.

6 seconds sound clip from the Rocky (1976) movie soundboard.

You can hear this line at 00:41:53.376 in the Blu-ray version of the movie.

Quote context

[...]

- You're a pretty good skater, are you?

- You know, like I was saying before on the way over here. Fightin' used to be tops with me, but no more, you know?

- All I wanted to do at a fight was prove I was no bum, that I had the stuff to make a good pro, you know?

- You never got the chance?

- Hey, I ain't cryin' about it, 'cause I still fight. I kinda do it like a hobby.

- I tell you what the trouble is... I'm a southpaw.

- What's a southpaw?

- A southpaw means you're left-handed. And a southpaw throws your timing off, you see.

- Other guys it throws their timing off, makes them look awkward. Nobody wants to look awkward.

- You know where southpaw came from? No? I'll tell ya. A long time ago, there was this guy, maybe a couple hundred years ago, he was fightin' around Philadelphia, and he was left-handed, and his arm was facing towards New Jersey, you see, and that's south.

- So then that's why they call 'em southpaw, you see? Southpaw, South Jersey. South Camden, southpaw. You know what I mean?

- I don't know. Things probably worked out for the best, don't you think?

[...]