Williams took issue with a fist bump between two officials after Denver running back C.J. Anderson scored his second of three touchdowns in the Broncos’ 24-17 win on Sunday.
The NFL players’ union has sent an open letter to team owners calling on the league to end the lockout of on-field officials.
Aiming to ensure NFL rules are enforced the same way from game to game, the league will consider making about 10 officials full-time employees next season.
The NFL is experimenting with an eighth on-field official at four preseason games. The NFL competition committee will evaluate video of the four games before deciding whether to add the official for the 2011 regular season.