Add Rob Ryan to the list of former Cowboys employees vouching for free agent Dez Bryant. During an appearance on FS1’s Undisputed, Ryan told the story of Bryant ruining a rookie cornerback’s career by humiliating him in practice to somehow illustrate that Bryant is all about football.

You hear that, NFL teams: Bryant is worth signing, as long as you keep him away from your rookie corners.

Now let’s ask the question everyone wants answered: Who is this mystery cornerback?

After intense research, we think we have the guy. A search of Pro-Football-Reference.com reveals that only four rookie corners played under Ryan during his time as Cowboys defensive coordinator, from 2011 to 2012: Morris Claiborne, Vince Agnew, LeQuan Lewis and Mario Butler.

Claiborne is the only one who played in 2017. He was also the only player drafted by the Cowboys. The rest were undrafted free agents, so it’s unlikely that (a) they’d be running with the first-team defense on the opening day of camp and (b) that Ryan would consider ruining the career of an undrafted free agent “the dumbest thing [he] ever did.”

And there’s this 2012 report from NFL.com:

“The Cowboys traded up to select the LSU cornerback in April’s draft, claiming they’d given him their best grade for a defensive prospect since Deion Sanders. They aren’t wasting any time putting him out there. Claiborne worked with the first team during the opening practice, which is something he’ll continue to do. He’ll be challenged throughout camp by the Cowboys’ receivers, and he’ll make mistakes. (Bryant has been making life difficult for him.)”

We can’t say with absolute certainty that Bryant ruined Claiborne’s career, but he probably did. At least in Ryan’s mind. Unlike, Bryant, Claiborne currently has a job. He signed a one-year, $7 million deal with the Jets this offseason after playing for them in 2016.