Today's NFL is a passing game, and even if a team decides to primarily run the signal caller's role will not diminish.

Quarterback competitions can bring out the best or worst in NFL teams, but coaches need to know who can instill confidence and lead their team the best.

Check out five intriguing quarterback battles that could change the trajectory of each team as the 2012 season plays out.

Carson Palmer Oakland
The Oakland Raiders may not have a suitable replacement for Carson Palmer on the roster. Reuters
Arizona QB Kevin Kolb
Kevin Kolb lost his job to John Skelton in 2011. Reuters
Tampa Bucs QB Josh Freeman
Josh Freeman may have run out time in Tampa. Reuters
Ryan Tannehill will start his first career NFL game on against the Panthers.
Miami quarterback Ryan Tannehill started all 16 games of his rookie season last year. winsnlosses.com
New York Jets QBs Mark Sanchez and Tim Tebow
There's a chance both Tim Tebow and Mark Sanchez will be former Jets in Week 1. Reuters
New York New York Arizona Arizona