The New York Giants have been the model of consistency in the NFL for over 25 years, but it has become apparent that changes are needed to restore the franchise back to the top of the NFC. 

The entire organization (front office, coaches and players) is to be blamed for another dismal season. It will be the fourth time in the last five seasons that the Giants have missed the playoffs. Massive changes are expected this offseason, and the biggest move could come to the head coaching position. 

Team management must decide if Tom Coughlin is the man to lead the Giants in the team's next chapter. He's three years removed from 70-years old, and Coughlin must be honest with himself if he truly wants the job of rebuilding the Giants back to dominance. The future Hall-of-Fame coach deserves to leave on his own terms, but the Giants like every NFL franchise has a short list of potential head coaching candidates.

Here are five big names to replace Tom Coughlin:

Mike Sullivan

Mike Sullivan isn't a household name, but he did receive some interest from the Chicago Bears for their head coaching position before they selected Marc Trestman last offseason. Sullivan seems to be the logical choice to replace Coughlin, as he coached under him (the Giants quarterback coach from 2010-11) for eight years before leaving New York to become the offensive coordinator in Tampa. 

The one negative in hiring Sullivan is that some front office executives feel his coaching style is too similar to Coughlin; a coach that's very disciplined and expects perfection on every play. His hire might hinge on how much credit Sullivan receives for the rapid development of Tampa Bay Buccaneers quarterback Mike Glennon into the starting lineup. 

John Fox

There has always been a mutual attraction between John Fox and the Giants, as he was the team's defensive coordinator during the Jim Fassel regime. 

Historically, the Giants have always hired head coaches that have some connection with the organization, and Fox most likely would have become the team's head coach already if he hadn't done a terrific job with the Carolina Panthers. His contract with the Denver Broncos expires after next season, but if the team wins the Super Bowl this February, you could see a mass exodus (quarterback Peyton Manning???) from the Mile High City.  

Bill O'Brien

Publicly, Penn State Nittany Lions head coach Bill O'Brien has stated several times that he will return to the school for the 2014 season, but numerous media sources have reported that O'Brien is open to listening to NFL job offers this offseason. 

The attraction for the Giants is the pro game has demanded successful teams be more creative offensively, which is O'Brien's expertise. It's no secret that the Giants offense (ranked 30th in points scored) has been dysfunctional all season, and it's the right time for a new voice inside the lockerroom. O'Brien's resume is impressive, as he was apart of the New England Patriots coaching staff that went to the Super Bowl in 2007 and 2011 (offensive coordinator). If the Giants offer him the job, it will be difficult for O'Brien to turn them down. 

Bill Cowher

The speculation surrounding Bill Cowher eventually replacing Tom Coughlin as the next head coach of the Giants has hung over the franchise like a black cloud since the day he resigned from the same position with the Pittsburgh Steelers in 2006. 

You get the feeling that Cowher has no sense of urgency to leave his cushy TV gig for another opportunity to walk the sidelines. There have been plenty of opportunities offered to him, but Cowher hasn't pulled the rip cord yet. The temptation of coaching quarterback Eli Manning back to elite status and winning another Super Bowl could be enough to lure Cowher out of retirement. 

Bill Belichick
The reality of Bill Belichick leaving the New England Patriots for the New York Giants might be the longest of long-shots, but his name has always been atop the Mara's wish list for their head coaching position. 

Often, Belichick speaks fondly of his time with the Giants, as he spent 12 years with the team, beginning as a special teams coach on Ray Perkins coaching staff in 1979 then leaving for his first head coaching position in Cleveland as the defensive coordinator of a Super Bowl champion. His resume as a head coach speaks for itself; Belichick has lead the Patriots to three Super Bowl titles and is the chief architect of one of the true dynasties in the NFL.