The 2013 NFL regular season was grueling. Perennial losers like the Detroit Lions, Oakland Raiders and Cleveland Browns didn't show up at all. They didn't even seem to aspire to a .500 record. As a result those teams' players and staff are sitting home watching the playoffs unfold. For many other squads in the league winning a Super Bowl is a constant goal. Out of the 32 teams in the National Football League, only four remain standing heading into Championship Sunday.

They are the Denver Broncos, the New England Patriots, the Seattle Seahawks and last, but certainly not least, the San Francisco 49ers. Each of these teams deserve to play in the Super Bowl, but alas, only two can move on. Failure is no option. Win and move on. Lose and live with the what-ifs.

With Championship Sunday only a day away it's about time to analyze the four teams who are left standing. The most watched matchup will easily be the Patriots vs. the Broncos in the AFC Championship game at 3pm on CBS. Quarterback Tom Brady meets his nemesis, fellow gunslinger Peyton Manning, in a rivalry for the ages. Brady hopes to take the Patriots to the sixth Super Bowl in his career, and the seventh in franchise history. Manning would love nothing more than to return to the big game for the third time is his remarkable career. He also has more to lose. If he fails to take his Broncos to the Super Bowl all the "choke" talks will surface again. If Brady loses... well, he at least has three rings at home.

The NFC Championship game immediately follows the AFC game. It starts at 6:30pm and is also airing on CBS. This contest feels completely different to the battle of first ballot Hall of Fame QBs. That's because Russell Wilson of the Seahawks and Colin Kaepernick of the 49ers are squaring off under center. They are youngin's -- each has been in the league for just two years. Kaep didn't even start until taking over for an injured Alex Smith (now with the Kansas City Chiefs) midway through the 2012 campaign.

Another dynamic that differs between the AFC and NFC championships is the animosity the Seahawks and 49ers have for each other. Whereas Brady and Manning like each other off the field, Wilson and Kaep won't be having a brofest anytime soon. The Seahawks are hosting and the crowd noise will be deafening. Will 49ers coach Jim Harbaugh's tactic of practicing with blaring music help his offense, defense and special teams unit?

Who do you think will represent the AFC and NFC in Super Bowl 48? Let us know in the comments below.