The Seattle Seahawks have been fined $US400,000 ($A530,000) by the NFL and will forfeit their fifth-round selection in the 2017 draft for violating off-season workout rules.
The league fined Seahawks head coach Pete Carroll $US200,000 for his role in the violation while the team will also lose one week of organised team activities (OTAs) in 2017.
The decision to impose the punishments was made after the National Football League and its players association independently reviewed an on-field practice video filmed on June 6.
Both parties agreed that Seattle had violated the "no-live-contact" rule - a breach of the NFL-NFLPA collective bargaining agreement.
"Voluntary off-season workout programs are intended to provide training, teaching and physical conditioning for players," the NFL said in a letter sent to the club.
"The intensity and tempo of drills should be at a level conducive to learning, with player safety as the highest priority, and not at a level where one player is in a physical contest with another player."
The Seahawks were also told that any further violations would "likely result in significantly higher fines, the cancellation of future OTA days ... as well as the forfeiture of higher-round or multiple draft selections."
