American Football: Where do the black lines on the face come from?

[madd-hatter]

I've always wondered...

[PixilEyes]

To keep the sun/stadium lights out of their eyes.

[nexx]

It reduces glare although I'm not entirely sure how it works.

Cheetahs also have black fur under their eyes for the same reason.

[User6060]

plus it looks tough :p

[IlliniPi]

The stuff is called eyeblack....ch-ch-ch-check it out.

http://www.eyeblack.com/

and

http://en.wikipedia.org/wiki/Eye_black

[randy_tho]

http://en.wikipedia.org/wiki/Eye_black

[bayrider]

I saw it on Man vs Wild. Bear Gryls rubbed charcoal from a camp fire under his eyes in the Sahara.

eyeblack dates centuries apparently.

[L3thal]

Good stuff. I wasn't even sure why they used it but now that explains it all.