Help me translate this, please

I work as a subtitle translator, English to Dutch.
Can somebody tell me what 'to convert in the red zone' means, in a context of American football?
All help will be greatly appreciated!
edit: an explanation in English will be enough, you don't actually have to translate in into Dutch
Thanks!
Edit 2: never mind, found it!
Can somebody tell me what 'to convert in the red zone' means, in a context of American football?
All help will be greatly appreciated!
edit: an explanation in English will be enough, you don't actually have to translate in into Dutch

Thanks!
Edit 2: never mind, found it!