The-Hogs.net - Washington Football Discussion, Redskins to Commanders Era

I just watched the replay of the Chiefs/Raiders finish: Chiefs ball on the one with five seconds left on the clock. Larry Johnson clearly breaks the plain of the goalline with three seconds left, but the clock winds down to zero. I also noticed a similar situation in Super Bowl XXXVI, when Vinateri's kick went through the uprights with a handful of seconds left, but the clock also expired.

Shouldn't the clock stop as soon as the ball crosses the endzone or uprights? Is this just a poor job by the scorekeeper, or is there a rule I'm not aware of?

There are also rules about how much time is run off the clock for certain things, particularly field goals.