Sam Darnold's 639 spin rate: Seahawks QB is a 'geek' on tight spirals

Darnold, in his second season with Seattle, appeared alongside the team's passing game coordinator and one of his primary receiving targets to discuss the mechanics behind the stat. The NFL was compelled to post part of the segment on Instagram.

Wide receiver Cooper Kupp said he used to think too much spin made the ball harder to catch. "I've now caught the ball from Sam for a year and a half, and now I'm not so sure," Kupp said with a smile.

Darnold said he has been working on throwing a tight spiral since he was a kid tossing a football in the yard with his dad. Now when he generates a whip with his arm and the torque needed to throw the ball efficiently, he thinks about what's ahead, particularly later in a season when weather can have a huge impact on the football.

The episode featured an extended shot of one of Darnold's passes in flight, set to a remix of the 1984 new wave hit "You Spin Me Round (Like a Record)" by Dead or Alive. HBO Sports is especially adept at capturing compelling footage on "Hard Knocks." While Seattle, the Pacific Northwest and the Seahawks VMAC training facility on Lake Washington all make for a beautiful backdrop, the shot of Darnold's pass is totally on target.