defensive offside question

[mcrowder]

That's exactly it. Ball spots are rounded to the nearest yard, as are yardages-to-gain for the first. In rare cases, because of these two factors, and the fact that they do not EVER round to the zero (either at goal lines or first downs), you will see weirdness like this - and it will be statistically recorded like this. Add up all the penalties for Oakland, and this one will be "officially" counted as 4 yards.

See also - ball outside the 5, going in (but not outside the 5 1/2). Runner gains slightly over 5 yards, landing on the inch line. This runner gets "credit" for 4 yards, as the ball is still listed on the 1, officially.