Coach

Coach is one of the four playable survivors in Left 4 Dead 2. Coach was a high-school football instructor for a well playing team, but he suffered a nasty knee injury. Ironically, he's now a health teacher pushing 40 years old, but he's gone to seed since his collegiate glory days. The zombie apocalypse makes him wish he'd watched his own fitness more closely. Faliszek says Coach has "a great hatred for a few of the zombies—the Witch in particular," but naturally, he wouldn't explain why.

Quotes
"See: Coach/Quotes"

Trivia

 * Many players assume that Coach is Bill's Left 4 Dead 2 counterpart.
 * Many people relate Coach with the character Uncle Phil from the TV show The Fresh Prince of Bel-Air. He also resembles Bubb Rubb of "whistletips" fame.
 * Coach appears to have a slight speech impediment, occasionally dropping his R's and G's. This is probably due to Southern dialect.
 * He may also be somewhat religious as he usually makes comments referring to the Bible and stating the last time he saw his grandmother, she asked if he was still a praying man.
 * According to their back-stories, both Bill and Coach have knee injuries.
 * "Though I walk through the valley of the shadow of death" was originally a quote from the Bible, Psalms 23:4.
 * In an issue of PC Gamer, the original concepts of the Coach can be seen, including a skinny coach, a white coach, and a coach in football shoulder pads used as armor. He also holds a Bow and Arrow.
 * Coach's default weapon may be the AK-47 probably because he is seen holding one in every campaign poster, except for Dead Center and Hard Rain.