The 2012 NFL rulebook leaves little doubt.
"A team is allowed three charged team timeouts per half," it reads.
Errors of officiating and administration conspired to give two NFL teams what amounted to a fourth timeout Sunday.
A replacement referee accepted blame for incorrectly reinstating the Seattle Seahawks' third timeout against the Arizona Cardinals in the final minute of the Cardinals' 20-16 victory. The error gave Seattle an opportunity to run the ball on first-and-goal from the 6 instead of passing to stop the clock. Had the Seahawks scored to win the game, Arizona would have become the NFL epicenter.
The Cardinals came out OK, but the St. Louis Rams weren't so fortunate.
A clock operator's failure to start the game clock while the play clock continued to run led the Rams, facing third down while protecting a three-point lead at Detroit, to use a timeout ahead of the two-minute warning, thus avoiding a delay penalty.
Had the game clock started on time, the Rams could have run that third-down play after the two-minute warning, putting pressure on the Lions to use their final timeout. As things turned out, Detroit used that timeout during its drive to the winning touchdown.
The error had nothing to do with replacement officials, Rams coach Jeff Fisher told reporters.
"It's a league hire, the clock operator," Fisher said. "They interact with the officials, but it’s a separate entity. They’re not part of the crew. This is not a replacement clock operator."