Of those free agents, several of them have medical concerns that other teams would likely prefer to evaluate in person. Brown is two years removed from knee surgery and has not regularly practiced the past couple of seasons. Shell has battled a litany of smaller injuries during his career. Green saw his 2020 season shortened by a neck injury teams are likely to want to evaluate prior to signing.
Further, even for a player like Penny who finished the 2021 season on an absolute tear, the simple fact of the matter is that many teams would want to do their own MRI on his surgically repaired knee. He obviously showed no signs of being slowed by the knee down the stretch in 2021, but teams are well aware of the long-term impact for running backs of a serious knee injury for running backs.
For example, Todd Gurley suffered a torn ACL in November 2014 while playing at the University of Georgia, and then just over four years later his production fell off a cliff in December 2018. After starting the 2018 season off with six 100 yard rushing performances in the first twelve games of the season, after a 23 carry, 132 yard performance against theon December 2, 2018, Gurley broke the 100 yard mark just twice over the final 33 games of his career.
This is obviously not to say that Penny, Brown, Green or Pocic will see the remainder of their career derailed by injury, as all of them played and played well at times during the 2021 season regardless of their past injuries. However, those past injuries are the type that have the potential to pop up and cause issues again in the future, meaning it’s not unreasonable for a team to conduct an in house evaluation of those past injuries before making a commitment.