The Argentine first division, bloated by two champions per season for 21 years, will revert to crowning only one winner from the 2012/13 campaign starting in August.
The season will continue to be divided in two with the "Inicial" and "Final" tournaments replacing the current Apertura and Clausura but the winners of each will meet in a grand final, the Argentine FA said on its website on Wednesday.
The last time there was a single champion was when a young Marcelo Bielsa's Newell's Old Boys won the title, the third of the Rosario-based club's five, in 1990/91 in a two-legged final against Boca Juniors.
Since the advent of two championships per season comprising 19 matches each, now relegated giants River Plate boosted their record number of titles by 12 to 33 and arch-rivals Boca by eight to 24.
Racing Club, another of the so-called Big Five, ended a 35-year wait for their seventh title in the 2001 Apertura.
The system occasionally favoured smaller clubs with Lanus lifting their first title in the 2007 Apertura and Banfield two years later.
Boca, this season's Apertura title winners, are joint Clausura leaders with Newell's Old Boys on 25 points with six matches remaining.
The teams finishing top of the two halves of the season qualify for two of Argentina's five berths in the elite Libertadores Cup, South America's equivalent of Europe's Champions League.
An AFA board meeting on Tuesday night also confirmed there would be three teams relegated, using the current system, with those with the worst points averages over three seasons going down.
Several countries in Latin America followed Argentina into a system of Apertura and Clausura in the 1990s although in South America some are played in the calendar year from February to December.comments