Under-the-radar NFL trade candidates: 20 players with sneaky trade value to watch, including Christian McCaffrey, Calvin Ridley

It feels like anything is possible on the NFL trade market. Teams are more willing than ever to part with top-shelf players or even top draft picks who haven't earned patience.

Last offseason saw four starting quarterbacks -- Matthew Stafford, Jared Goff, Carson Wentz and Sam Darnold -- switch homes via trade. That activity feels like a mere appetizer for this cycle. Several top passers could be on the move, including Aaron Rodgers, Russell Wilson and Deshaun Watson.

But we're instead here to outline sleeper trade candidates -- some obvious, some not. That means players who have failed to meet expectations or met enough to get paid too much. They need scheme changes or might be wondering why they aren't utilized correctly. Teams draft bad fits and begrudgingly admit the mistakes, realizing that clinging to hope too long can affect market value and morale in the locker room.

Most franchises are still emerging from the haze of the season and aren't combing this market yet. But it's never too early to set the stage for March 16, when trades can be consummated at the start of the league year. That's why we reached out to execs, coaches and veteran agents on what this market might look like. This isn't to predict trades or even suggest that these players will be moved but rather to outline names that come up in conversations. Here are 20 sleepers who could be part of trade discussion over the next two months, for one reason or another.