Gimnasia join River Plate in second tier
Record 33-time champions River were relegated on Sunday after a similar 1-1 result in the second leg of their relegation-promotion play-off put them out 3-1 on aggregate against Belgrano and sparked riots inside and outside the Monumental.
Gimnasia, who had lost the first leg in San Juan 1-0 on Sunday, fell behind in the opening minute of the second leg to a lobbed goal by winger Sebastian Penco.
The La Plata side, captained by veteran former Boca Juniors and Columbus Crew striker Guillermo Barros Schelotto in his last match before retiring, equalised through Jose Vizcarra 22 minutes from time.
Both sides finished with 10 men after Gimnasia's Milton Casco was sent off in the 67th minute for a second booking and Penco earned a second yellow card 10 minutes later.
Gimnasia, who had survived similar play-offs the two previous seasons, were relegated for the first time in 30 years.
River, who had never been relegated before, boosted the ranks of former champions in the Nacional B where Rosario Central, Chacarita Juniors, Quilmes and Ferro Carril Oeste now play.