What if the last two in Serie A are equally divided?

Don't calculate the goal. According to the regulations of the Serie A Football Association, if the final points of the two teams are the same, we must first count the mutual achievements of both sides, that is, the relationship between victory and defeat. If they are the same, the goal difference between the two teams will be counted directly. If they are the same, we should count the goal difference of the whole season. If they are the same, count the total number of goals scored by the two teams respectively. If this is the same, draw lots to decide the ranking. Therefore, we don't count the home and away goals, only the goal difference between the two teams. According to your situation, the result can only be determined by counting the goal difference or the total number of goals scored by the two teams throughout the season or even by drawing lots, but there will be no play-offs.