The National Football League may have a trade deadline, but NFL free agency goes year-round.

Sometimes, it's time for a team and player to break up, and occasionally, teams lose faith in a certain player. Often times, the team is correct, but sometimes the released player excels in a different uniform.

While the NFL season looks ready to start in September, there are still several key players up for grabs. Here's the best free agents remaining:

Jermichael Finley

Finley played six seasons for the Green Bay Packers. He helped the Packers win a Super Bowl and for a long time, he was a great tight end. Unfortunately, Finley has had knee problems in his career. In 2010, he missed 11 games and just last season he missed 10 games. Finley could be worth a small investment for a team that needs a tight end.

Josh Freeman

Freeman is an underrated quarterback who had a rough 2013 season. Freeman holds numerous Tampa Bay Buccaneers franchise passing records, but he didn't get along with Head Coach Gregg Schiano. In 2010, Freeman threw 25 touchdowns and just 6 interceptions with a 95.9 passer rating. In his last full season, 2012, he threw for over 4,000 yards with 27 touchdowns and 17 interceptions. Freeman is only 26 years old and could help many teams. The Minnesota Vikings, Houston Texans, Jacksonville Jaguars, and Buffalo Bills could certainly give Freeman a try.

Dustin Keller

Keller has had some really good moments in the NFL, but he didn't play a single game last season. The Miami Dolphins gave him a chance last year, but the 29-year-old tight end tore his ACL in the preseason. Keller played very well for the New York Jets, especially considering Mark Sanchez was the quarterback. Keller could be worth a one year offer for a team that needs a tight end.

Ed Reed

Ed Reed is one of the greatest safeties in NFL history. The nine-time Pro Bowler made a huge name for himself playing for the Baltimore Ravens and eventually won them a Super Bowl. Unfortunately, Reed will be 36 years old when the season begins and he has lost a step. Regardless, Reed is still a good safety who brings leadership and elite field vision.

James Harrison

For a few seasons, Harrison was one of the best linebackers in the league and helped the Pittsburgh Steelers win two Super Bowl titles. For a seven-year span, he was the hardest hitter in the entire league and he often paid for it, out of his pocket. He made one of the biggest plays in Super Bowl history against the Arizona Cardinals with his interception off Kurt Warner. Harrison is still a hard hitter who can play the middle of the field as well.

Asante Samuel

For a long time, Samuel was one of the best ball hawks in the game. He would take big risks and would frequently capitalize by intercepting quarterbacks. Samuel is now 33 years old and although his speed has decreased, he still has some of the best hands in the game. Samuel has led the NFL in interceptions twice, doing so on two different teams.

Santonio Holmes

The former Super Bowl MVP is still a free agent. Similar to Keller and Finley, the reason is health. Over the last two seasons, Holmes has had multiple foot injuries but he did have almost 500 yards last year. Holmes was a first round pick who would be the Super Bowl hero for the Steelers.