yeah that is lag, but i have also seen glitches.
Offside gliches, happened to me 2 times in 43 online games;
ref blows for offside, when im not even close to being offside(no, im not speaking of the typical bad ref decisions that we all probably know of).
Actually, i don't have to make a pass at that point, and when the replay shows, the line turns red when im still running with the ball. And in the rest of the replay, it's just random what happens, meaning it can happen even if you don't make a pass at all.
Anyone else seen this?
Edit*
Well, it could possibly be lag, but it doesn't look like it at all ..