Oakland Raiders head coach Jon Gruden, center, watches as players stretch during practice at the team’s NFL football training facility in Alameda, Calif., Tuesday, May 29, 2018. (AP Photo/Jeff Chiu)

Oakland Raiders head coach Jon Gruden, center, watches as players stretch during practice at the team’s NFL football training facility in Alameda, Calif., Tuesday, May 29, 2018. (AP Photo/Jeff Chiu)