The NFL is a business, and just like any business it is sometimes important to let people go in order to move the company forward. The San Francisco 49ers did it with Joe Montana, despite Montana leading the 49ers to four Super Bowls.
Unfortunately, these "divorces" don't always end up with both sides remaining friends. Sometimes they can get ugly. Real ugly.
Here are the ugliest divorces in NFL history.
If we're talking about NFL divorces, what better place to start than with Brett Favre and the Green Bay Packers?
This union was love at first sight and lasted a sweet, and sometimes sour, 16 seasons before the two parties decided to part ways. When it first became clear that the Packers were ready to move on from Favre, it appeared as if both parties were going to move on in relative peace.
Favre's retirement press conference was filled with tears, and you could tell that the decision was a difficult one. Then, out of nowhere, disaster struck. Favre decided he wasn't completely done with football and signed with the New York Jets.
As if it wasn't bad enough seeing Favre in a different color green for Packers fans, it got even worse when he signed with the Minnesota Vikings before the 2009 season. It was the ultimate act of betrayal, and one that Green Bay's fans will never forget.
Any hope of these two parties reconciling was thrown out the window the second Favre put on that purple jersey.
I'm just guessing here, but I'm thinking that Al Davis wasn't an easy man to work with while he was walking the Earth.
Former head coach Lane Kiffin found that out rather early in his coaching career with the Oakland Raiders and Davis. It all started when Kiffin didn't want to draft JaMarcus Russell with the first pick of the 2007 NFL draft. Davis disagreed, and from that point on tensions just continued to build.
It was only 20 months later that Davis called Kiffin on the phone to let him know he was being fired. He then went on to call Kiffin numerous names during a press conference on the firing. This bickering back and forth went on for a while after Kiffin was fired.
While they never got over their differences, Kiffin did have some nice words to say after Davis had passed away, per Steve Corkran via ibabuzz.com.
This relationship between Jay Cutler and the Denver Broncos started going sour once the Broncos showed interest in Matt Cassel following the 2007 season. As the starting quarterback of the Broncos, Cutler wasn't too happy about bringing in competition.
He asked to be traded and finally got his wish when the team shipped him off to the Chicago Bears. At the start of the 2008 season, it seemed that the Broncos got the better end of the deal, picking up a load of draft picks and a competent starter in Kyle Orton.
However, Cutler has righted his ship in Chicago and has made the Bears one of the better teams in the NFC, while the Broncos have been mediocre at best.
Via sportscolumn.com, when you call a teammate's sexuality into question during an interview, it is likely that your relationship with your team isn't going to end very well. That is exactly what happened with Terrell Owens and the San Francisco 49ers following the 2003 season.
Owens had already distanced himself from the team, but his comments were the final straw. The team looked to trade him and actually thought it had a deal in place with the Baltimore Ravens. They'd trade Owens for a second-round draft pick.
However, there was miscommunication about Owens and his free-agency standing, and Owens had already been in contact with teams, specifically the Philadelphia Eagles. Court battles ensued, and when all was said and done, Owens was a member of Philadelphia for the start of the 2004 season.
Despite Owens starting his career out with a bang, it wasn't too long until he wore out his welcome...
...And eventually Terrell Owens had his second divorce with another team in a short period of time.
It was only two years until the Philadelphia Eagles could no longer put up with Owens and his antics. It started with him complaining about his contract. Had that been all that Owens had issues with, the parties would have likely been able to figure out their relationship.
However, Owens continued to speak, especially about his quarterback, Donovan McNabb, and this earned him a four-game suspension without pay. Things didn't get better, and the Eagles eventually deactivated him for the remainder of the season.
Following the 2006 season, the Eagles flat-out released Owens and let him take his issues to another team.
When Randy Moss is focused, he is one of the greatest wide receivers to ever play the game. This is evident by his record 23 touchdown receptions in one season.
Unfortunately, there have been numerous times when Moss has lost his focus. The first time happened with the Minnesota Vikings when he had issues with the amount of touches he was getting during games.
During the 2004 season, his last with the team, Moss recorded career lows for receptions and yards. He also missed three games with "injuries."
Moss eventually moved on to the Oakland Raiders, where he wore out his welcome even quicker than with Minnesota.
Michael Vick was the bright future of the Atlanta Falcons' franchise. He led the team to the playoffs during the 2002 season and completed one of the greatest upsets in history when he walked into Lambeau Field and beat the Green Bay Packers in January.
However, it all went downhill from there. Vick struggled with injuries in the following seasons and was never able to get the Falcons deep into the playoffs. It continued to get worse when Vick was arrested for his involvement with dog fighting.
At that point, the Falcons wanted to get as much distance between them and Vick as possible. They brought in a new quarterback the following year in Matt Ryan so fans could forget about Vick even quicker.
Both sides have finally forgiven each other, making this one of the best divorce endings on this list.
Art Modell versus the Cleveland Browns is easily the ugliest divorce in the history of the NFL.
Not only did Modell have secret meetings concerning moving the team to Baltimore, but he also did it while the city was figuring out how to build the team a new stadium. In fact, it was just a few days before Cleveland was set to announce its plans for how it would build a new stadium for the Browns that Modell announced his decision to move the team to Baltimore.
Of course, the fans in Cleveland weren't too thrilled when they heard about Modell's plans. The city would eventually sue Modell for breaching contracts about the Browns playing games in Cleveland.
When the parties finally settled, Modell had the Baltimore Ravens, which turned into one of the most successful franchises in the NFL. Cleveland finally got its team back, but Modell has definitely walked away with everything good from this divorce.