The training camp for NFL teams is now underway. While not all players have reported to their respective teams, they are expected to soon. For the most part, most teams are likely set with their current rosters minus a few additions. It makes sense given that the preseason will be underway in less than two months' time.

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With that being said, some teams will still bring in some players to help fill out their rosters and fill the holes they have open. However, there are many well-known NFL free agents who won't be signed by any NFL teams for the upcoming season.

10 Earl Thomas

Earl Thomas
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Earl Thomas has to be one of the greatest players in league history to never get a shot after one bad stint. While in Seattle, he was one of the best safety and defensive players in the league. Even when he was in Baltimore, he was still a great player.

However, his terrible attitude lead no teams to want to touch him after his release from Baltimore in August 2020. While some speculated if he would get signed by the Houston Texans after recent talks, an arrest last month has likely scared teams off for good.

9 Tim Tebow

Tim Tebow Jags

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Tim Tebow's attempt to convert to tight end last year was admirable, but it just didn't work out. He was released following the preseason in Jacksonville and wasn't signed by any other team. However, he's still in a shape, maybe someone will give him a shot this season?

No, no chance. Apparently, Tebow has kept himself in shape in the hope that some team will give him a call. However, with his underwhelming training camp last year with the Jaguars, don't expect to see him on a field again.

8 Robert Griffin III

Robert Griffin III Ravens
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Last year, Robert Griffin III decided to sign with ESPN in order to become a broadcaster. While he's killed it in the booth, he's also had a clause in his contract allowing him to leave at any time in order to sign with an NFL team.

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However, since his release from the Baltimore Ravens last year, no team has even brought him in for a workout. While Griffin III's grit and ability to stick around in the league despite his injuries is admirable, it's unlikely that he will play in the league again.

7 David Johnson

David Johnson Texans

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David Johnson has the unfortunate pleasure of being on the wrong end of one of the worst trades in NFL history. The Houston Texans famously swapped the former Pro-Bowl running back for DeAndre Hopkins in 2020, in a deal that blew up badly for the Texans.

Even though the Texans dealt the greatest player on their team for Johnson, even they couldn't convince themselves he had much left in the tank. On the wrong side of 30, with all the injuries he's had, his career in the NFL is likely done.

6 Dustin Colquitt

Dustin Colquitt punt
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Dustin Colquitt was one of the best punters in the league during his time on the Kansas City Chiefs from 2005 to 2019. Since that time, however, he's very clearly declined as he's gotten older. The former Pro-Bowler turned 40 earlier this year.

While it's not uncommon for punters and kickers to play until that age, Colquitt has struggled badly for the past two years. His last stint on the Cleveland Browns was especially hard to watch. At this age, with his clear decline, it's likely time for him to call it quits.

5 Adrian Peterson

Adrian Peterson
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Adrian Peterson is one of the greatest running backs of all time. However, since his departure from the Minnesota Vikings in 2017, he's gone through the team after team in an effort to stick around in the league.

Up until now, he's been successful. However, he's now 37 years old and is coming off an injury that ended his year with the Seahawks last season. If that wasn't enough, he also had a recent arrest for domestic violence earlier this year.

4 Le'Veon Bell

Le'Veon Bell
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Le'Veon Bell has seemingly done a speedrun in ways to screw up his NFL career. After sitting out a year in Pittsburgh in order to get a new contract, he then signed with the New York Jets but was released after struggling badly.

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He then went through the Kansas City Chiefs, Baltimore Ravens, and Tampa Bay Buccaneers in the span of a year. He famously blamed coaches such as KC's Andy Reid for his struggles, which likely put off other teams. To his credit, Bell has likely given up hopes of playing in the league again, which is why he's prepping for a move to boxing.

3 DeSean Jackson

DeSean Jackson
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DeSean Jackson has been in the league for seemingly forever but is somehow only 35 years old. Although, the last few years haven't been kind to the former All-Pro, as he's gone through the team after team over the past few seasons.

Jackson himself has debated retirement recently, confessing he's not sure if he'll play again. With the former star himself doubting his future, it's unlikely anyone else will give him a shot.

2 Cam Newton

Cam Newton Panthers

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Cam Newton is a former MVP and face of the league. However, the last few years have been hard to watch, as he's struggled with injuries and had extremely poor play when he has been on the field.

Newton doesn't have the type of football IQ that helps as a backup quarterback, hence his being unsigned until now. With his poor play on the field, no team will sign him to be a starter either. It's a bit of an unfortunate end to a player who once seemed destined to win a championship.

1 Antonio Brown

Antonio Brown Tampa Bay

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Antonio Brown has gotten opportunity after opportunity. His play warranted it, after all, as he was one of the best receivers in the league. However, it seems that his luck has finally run out after his recent release from Tampa Bay.

Brown has the talent to not only stay in the league but be arguably the greatest player on a team. However, with all of his off-the-field issues, his time on the field seems over.