While Cruzeiro maintained their strong start to the Copa Libertadores group stage with a 3-0 win over Mineros de Guayana, River had to settle for their fourth consecutive stalemate in South America's premier club competition, drawing 2-2.
Colombian striker Teofilo Gutierrez inspired River's recovery mission after they trailed by two goals with four minutes remaining, scoring the Argentine visitors' first goal and setting up the equaliser.
After Egidio Arevalo and Damian Alvarez scored either side of half-time to put Tigres in control, a defensive mix-up in the 87th minute saw River striker Rodrigo Mora one-on-one with the goalkeeper and although the Uruguayan's shot was saved, Gutierrez tucked home the rebound.
River had Gabriel Mercado sent off in second-half stoppage time but the draw would have been little consolation for Marcelo Gallardo's men, as it left them two points behind second-placed Juan Aurich in Group Six with one game left.
In Belo Horizonte, Cruzeiro struck twice in the opening quarter of an hour to set up their win over Venezuela's Mineros.
