River Plate fans vented their fury at coach Daniel Passarella and his players and fought with each other after watching their team lose 1-0 at home to Estudiantes on Sunday.
Midfielder Ezequiel Maggiolo headed the only goal in injury time to effectively end River′s hopes of winning the Clausura championship.
The goal, which kept defending champions Estudiantes in the title hunt, came after a dramatic finale in which River defender Danilo Gerlo missed a gilt-edged chance and his team mate Marco Ruben had a goal disallowed for offside.
River played nearly the entire second half with 10 men after Ariel Ortega was sent off for a second bookable offence.
During the match, River fans fought with each other in a section of the stadium occupied by the hardcore supporters.
The defeat came a month after River were knocked out of the Libertadores Cup in the group stage by Venezuela′s Caracas FC.
Passarella, captain of Argentina′s 1978 World Cup winning team, made a brief appearance before reporters but refused to answer questions.
"They tell me there are problems outside and it′s not a good moment to talk," he said.
On Friday, Argentina′s Interior Ministry slapped a two-match home ban on River for incidents following their 1-1 draw at home to Independiente.
River have already served a previous three-match home ban this year because of fighting among their notorious supporters.
The defeat sent River down to fifth in the table with 26 points, nine behind leaders San Lorenzo with four matches each to play. Estudiantes are third with 32 points, behind Boca Juniors on goal difference.
San Lorenzo stayed on course for the title by winning 1-0 at Newell′s Old Boys with a second-half goal by defender Sebastian Mendez on Saturday.
Boca kept up the chase by winning 2-1 at bottom club Quilmes.
Jesus Datolo and Rodrigo Palacio scored in a five-minute spell to put Boca in control. Diego Torres pulled one back for the Brewers before halftime.
Struggling arch-rivals Racing Club and Independiente drew 1-1 in their derby, keeping both teams in the bottom five.
Facundo Sava, released by an incisive pass from Maximiliano Morales, opened the scoring for Racing in the ninth minute before Guillermo Rodriguez equalised in the 26th minute.
The weekend′s 10 games produced only 14 goals, with four matches ending goaless.
