The solitary point was not enough to give desperate River some breathing space as they battle to improve their poor three-season average and keep their heads above the drop zone.
River are just above the bottom four with two matches to go in Argentina's Clausura championship, but should they slip into the zone they would face a play-off against a second division side.
With his team having made little headway in the first half, River coach JJ Lopez took off two midfielders at half-time and sent on centre-forwards Mariano Pavone and Gabriel Funes Mori to join Leandro Caruso in a three-pronged spearhead.
The decision appeared to have backfired dramatically when wily 38-year-old striker Esteban Fuertes, the oldest active player in the Argentine top flight, put Colon ahead just before the hour-mark, side-footing past goalkeeper Juan Pablo Carrizo.
River pressed for the equaliser, raining crosses into the box and into the grateful hands of Colon keeper Diego Pozo.
However, with nine minutes left River snatched an equaliser, "Tank" Pavone passing to Funes Mori in front of goal, and when the youngster missed the ball it ran loose to Caruso and he blasted it home to wild cheers from River fans packing the Monumental.
Boca Juniors came from two goals down to draw 2-2 at relegation candidates Quilmes, striker Martin Palermo scoring from 30 metres in the 62nd minute and midfielder Cristian Chavez hitting the equaliser four minutes later.
The title race continues on Monday when leaders Velez Sarsfield host third-placed Godoy Cruz while Lanus, who are second, visit Independiente.
Saturday's match in Rosario between Newell's Old Boys and San Lorenzo was suspended after a police officer was shot and wounded.
It was the third match suspended due to fan violence in the 19-round Clausura, the second of two championship in the season.
