A little bit late, but here it is. 6 periods can be won during the regular season. These 6 teams, including the number 17 and 16 play in the play offs for staying/promoting to the dutch eredivisie. For example MVV played against De Graafschap (number 17) at home first. They lost with 3-2. Second game was at home at the Graafschap. The match ended 2-2. Had it been a victory for MVV, didnt matter what result, then there had to be played a 3rd match. This was the defining match. But now De Graafschap will have to play RKC. Again with the same system. The one who wins, will be in the Eredivisie next year. Same goes for the other teams. Roda will have to play Cambuur or Zwolle, who have to play a 3rd match.