With thanks to team photographers and Getty Images, here are photos of NFL officials in action in Week 4. Click on a photo to begin the gallery.
Walt Anderson (Kansas City Chiefs)
Clay Martin and his crew (Green Bay Packers)
Mark Pellis (Dallas Cowboys)
A partially obscured Jerod Phillips and referee Clay Martin (Green Bay Packers)
Mike Weatherford (Oakland Raiders)
Brad Rogers (Los Angeles Rams)
Craig Wrolstad (New England Patriots)
Tony Michalek (Los Angeles Rams)
Aaron Santi (Los Angeles Rams)
Byron Boston (Kansas City Chiefs)
Walt Coleman IV (Oakland Raiders)
Referee Brad Rogers (Los Angeles Rams)
Greg Bradley (Baltimore Ravens)
Derek Bowers and Scott Novak (Oakland Raiders)
Jim Mello (Minnesota Vikings)
Fred Bryan (Green Bay Packers)
Back judge Greg Steed (Los Angeles Rams)
Tony Michalek and Brad Rogers (Los Angeles Rams)
Steve Zimmer (Minnesota Vikings)
Nate Jones (Green Bay Packers)
Referee Clay Martin (Green Bay Packers)
Derek Bowers (Oakland Raiders)
Clay Martin tosses the coin (Green Bay Packers)
Referee Brad Allen (Minnesota Vikings)
Umpire Bryan Neale (Seattle Seahawks)
From Getty Images: