At the close of the group stage of the Diego Maradona Cup, Boca and River have a serious chance of ending up even in all areas used to break the positions. Thus, the draw is a latent possibility and, despite the versions, the teams with a tiebreaker game do not want to know anything.
The idea of a special meeting to define the finalist in San Juan would correspond to interests unrelated to those of the teams, which clearly have their heads set on the goal of the 2020 Copa Libertadores. Thus, neither of the two clubs is interested in defining the finalist with a tiebreaker match.
What has to happen for Boca and River to define the finalist by lottery?
Boca is currently the leader with eight points, eight goals for, and a +4 goal difference. River, meanwhile, appears with eight points, eight goals in favor, and a +3 difference. Further back comes Argentinos Juniors with seven units and although he cannot force a draw if he wins and the Millionaire does not, he will qualify.
With this scenario, the conditions that should be met so that both teams arrive evenly matched in everything would be: that both win their matches on the last date, that both convert the same number of goals in favor (which must be two, at least) and that River receives a goal against less than Boca.