At the international level and in professional games , there is no questions that the size of the goals should be checked on a regular basis ; and that both goals should be exactly 8 yards across by 8 feet high. However , having refereed close to 1000 games I have never measured or been asked to measure the goals . It was never mentionned during the many referee 's meetings that I attended and a measuring tape was (is?) not on the list of items that a referee carried . If one team had mentionned that one of the goals was bigger than the other we would play the game and I would make a report to the league who would decide if the result stood or that the game should be replayed ( I was provided forms to fill in case of field problems )
To tell you frankly , at the amateur level , I would be surprised to learn that half of the goals have the exact measurements !

Could be that Liverpool might be the only english team in the champions league quater finals !

Robert LaFrance

A peasant must wait a long time on a hillside with his mouth open , before a roast duck flies in . Chinese proverb