General view of River Plate's fans inside the stadium before the match. Photograph:( Reuters )
River said it was "incomprehensible" that the fixture should be played outside Argentina, although the club stopped short of saying they would refuse to play.
The troubled Copa Libertadores final between Argentina's two biggest clubs ran into more problems on Saturday when River Plate said they rejected the decision to face Boca Juniors in Madrid in the postponed second leg.
In the latest twist to the saga, River, the home team, said it was "incomprehensible" that the fixture should be played outside Argentina, although the club stopped short of saying they would refuse to play.
The hugely-anticipated match at River Plate's Monumental stadium in Buenos Aires was called off on Nov. 24 after the Boca team bus was attacked with stones and bottles as it approached the ground.
Several players were hit by shattered glass and some were affected by tear gas or pepper spray.
The match was rescheduled for the following day but was again postponed. The first leg in Boca's stadium had ended 2-2 one week earlier.
On Thursday the South American Football Confederation CONMEBOL announced the decision to move the game to Real Madrid's Bernabeu stadium on Dec. 9.
"River Plate reject the change of venue," the club said in a statement, adding that moving the game to Madrid "adversely affects those who bought tickets and also upsets the idea of equal conditions by taking away home advantage".
However, River did not say what action they would take if CONMEBOL stood by its decision.
River were fined $400,000 for the incidents and ordered to play their next two home matches in South American club competition behind closed doors. However, Boca have said they will appeal against the decision which they consider too lenient.
CONMEBOL ignored the appeals on Saturday and released information on ticket sales but although each team have been allocated 25,000, they must sell most of that allowance to fans outside Argentina.
"For security reasons local authorities have decided to give each team 5,000 tickets to sell to their fans in Argentina," CONMEBOL said.
The other 20,000 could be sold only to fans living abroad, CONMEBOL said in a statement. The teams must provide lists of the 5,000 names who buy the Argentina allowance.
Boca themselves were thrown out of the Libertadores in 2015 after River players were attacked with pepper spray by fans at halftime during the second leg of a knockout tie at the Bombonera stadium. Boca say they want the same standards to apply to River.
River said the attack on the bus happened outside the area which was considered the club's responsibility.
"The responsibility for the failure of the security operation was openly accepted by the highest authorities of the state," it said.
"It's incomprehensible that the most important fixture in Argentine football cannot take place in the country which is hosting the G20.
"Argentine football as a whole... cannot allow a handful of thugs to stop the Superclasico from taking place in our country."
It is the first time that the two clubs have met in the final of the competition, which is the South American equivalent of the Champions League.
From next season onwards, the final will be played in a single match at a neutral venue - a decision which CONMEBOL had already taken before last month's trouble.