NFL free agency is fast approaching and will start on March 16. While fans are often drawn to the big names, under-the-radar guys can turn into significant pieces on championship teams.

Winning a Super Bowl is very difficult, with so many contending teams in the league. Having depth and great pieces around the edges are often what separates elite teams from the rest of the pack.

Free agency is significant for teams, as it is perhaps the best way to upgrade the roster.

5 sneaky good free agents NFL teams need to sign

5. Arden Key – Defensive end

Key may not be a well-known name for NFL fans, but he had a solid season with the San Francisco 49ers. He was on a one-year deal worth around $1 million. He finished the season with 6.5 sacks and 17 quarterback hits. While he won't be a top pass rusher, he could add solid depth to any team.

Teams can never have enough pass rushers, and the 25-year-old Key would be a solid pickup.

4. David Njoku – Tight end

Njoku has shown flashes of brilliance throughout his career but hasn't developed into an elite tight end. He is set to become a free agent after four seasons with the Cleveland Browns, and a change of scenery in the NFL could be beneficial.

Last season, he had 36 receptions for 475 yards and four touchdowns. Although his numbers aren't great, Njoku has the talent to be a great tight end. Getting into a new situation could help him develop into a better player.

3. Emmanuel Ogbah – Defensive end

Ogbah has been an under-the-radar pass rusher for the Miami Dolphins over the past two seasons. He had nine sacks in each of the last two seasons, putting constant pressure on the quarterback. His ability to get to the QB makes him a valuable piece for defensive lines.

While Ogbah won't be a team's best pass rusher, he can be a solid secondary guy. Placing him next to an elite pass rusher would free him up to be an even better player in the NFL.

2. Connor Williams – Guard

Building an excellent offensive line is important for competing in the NFL Playoffs. The Cincinnati Bengals faced this fact in Super Bowl LVI, as the offensive line couldn't protect superstar quarterback Joe Burrow. He was sacked seven times in the game by the star-studded Los Angeles Rams defensive line.

Williams would be an upgrade for numerous teams to protect their quarterbacks and block in the run game. He is only 25 years old and could be a part of an offensive line for years to come.

1. Cedrick Wilson – Wide receiver

Wilson had some phenomenal games this season with the Dallas Cowboys. But the team has multiple elite wide receivers who overshadowed what Wilson can do. Last season, he had 45 receptions for 602 yards and six touchdowns. Considering he is the fourth wide receiver for the Cowboys behind Amari Cooper, CeeDee Lamb, and Michael Gallup, these are great numbers.

Wilson could thrive in a second or third guy on another team. He has the talent to play at a high level in the NFL alongside a star wide receiver. He is a solid route runner and has good speed, which leads to him getting open often. Whatever team picks him up will not regret it.

NFL free agency could shift teams into instant contenders, and sneaky good signings are always a good start.