Argentina. Transitional and, therefore, confusing season. The season calendar was changed from the “calendar year” to the “European calendar”. There were no more 2 separate championships, but singular league championship. To do that was to overcome problems – the original Metropolitan First Division remained as national one, but the second level had to incorporate provincial clubs and because of that practically played 2 championships in the inaugural 1985-86 – one was to determine which teams of the former Primera B Division will be part of the new Primera B Nacional. Thus, two confusing issues were and are at hand: The first one if the wisdom of the change of the season: looks like the prime motivation was to make possible to compete with European teams on equal footing, for so far there was the inconvenience one of the opponents to be on vacation between seasons and official games were difficult to schedule. Attached to that was the transfer market – South American rules were always laxer than the European ones, but it was becoming increasingly dangerous matter: players were transferred to Europe practically in the middle of the Argentine season. That often meant staring to build a new team right in the heat of unfinished season. Either that or no deal, for European clubs wanted new players before the start of their new season. And the Argentine clubs desperately needed transfer money. Aside from these 2 reasons, the change hardly makes sense: to play on European calendar means a season from August to May next year, which possible winter break. But seasons in South America are reversed and such a calendar means playing spring-fall season, like in Scandinavia. Since the Argentine summer is nothing like Scandinavian summer, the new schedule meant playing the central chunk of the championship in the scorching summer. Not a good idea, but it was done. Perhaps the biggest positive aspect was the incorporation of the whole country into one championship structure.
But transition was not easy – top level was accommodated easily and the old Metropolitan top division simply switched to new 1985-86 season. Second level was entirely different matter, as well as promotion to the top level. The old Metropolitan second division played a tournament called ‘Apertura’ in 1986. The top 8 teams in it were to play in the new Primera B Nacional, starting in 1986-87 season. The rest were going to third level, named Primera B Metropolitana, which included only affiliated clubs. The new Primera B Nacional was to be of 22 teams, so about 14 provincial clubs (depending on relegation from the top league) – presumably, those who qualified in the 1986 season. The structure of this tournament was largely as the one used for now defunct Nacional championship and the winner of it in 1986 was promoted to the top league for the 1986-87 season. Promotion from Apertura was more complicated: the second worst in the top division plus the top 7 teams in the Apertura went to play the Octogonal tournament – the winner of it was promoted to the top league for the 1986-87 season.
There was something lost in the transition from one structure to another: some famous clubs were nowhere to be seen: 
Belgrano (Cordoba) was one of them, apparently failing to reach promotion and having to settle in lower lever for the near future at least. But Belgrano was not all that heavy weight as the other absence: Racing (Avellaneda). What happened to one of the big 5 in Argentina? Not in the first division, not in the second… If Racing played in the Nacional, then why? It was Metropolitan club. If Racing somehow dropped out from the structure, then how they came back later? In 1986 Racing simply disappeared. But another great name came back:
Rosario Central (Rosario) earned promotion from the Nacional. It was fast recovery from failure, but so far they were only going back to the top division. It was going to be much better very soon, but for the moment it was satisfactory season – the shameful plunge down was over.