Mark Humphrey, AP
Kansas City Chiefs quarterback Alex Smith calls a play against the Tennessee Titans in the fourth quarter of an NFL football game on Sunday, Oct. 6, 2013, in Nashville, Tenn. (AP Photo/Mark Humphrey)

With the Seattle Seahawks and New England Patriots each losing their first game in week five, the number of undefeated teams left in the NFL dropped from five to three this past week. The Denver Broncos, New Orleans Saints and Kansas City Chiefs are the three teams that still haven't lost this season, and as the season progresses, that list will undoubtedly shrink.

On the flip side, the Jacksonville Jaguars, Tampa Bay Buccaneers, Pittsburgh Steelers and the New York Giants are all teams in the NFL that still haven't won a game.

Such extreme differences in the NFL win/loss records correctly reflect the way this season has gone so far: a lot of ups and a lot of downs. Here are the best and worst from week five in the NFL:

You can follow Mitch Kunzler on Twitter at @MitchKunzler.