River Plate are facing possible relegation from Argentina's Clausura for the first time in their history after defeat to second-placed Lanus condemned them to a play-off.

The Buenos Aires giants have won the league crown on 33 occasions, ten more times than fierce rivals Boca Juniors, but have been on the slide in recent years and have not done enough to ensure their safety. They lost 2-1 today, with Silvio Romero's opener cancelled out by highly-rated River prospect Eric Lamela, only for Leandro Diaz to steal it for the hosts in the closing moments.

While River remain well off the bottom clubs this term, their poor form over the last three seasons - as well as Argentina's complex relegation system - mean they now face a two-match play-off against second-tier side Belgrano.

Olimpo are safe after Martin Rolle's goal was the difference against Quilmes, who have been relegated automatically. Tigre have also avoided demotion following their 1-1 draw with Argentinos Juniors. Roman Martinez scored their leveller after Nicolas Blandi's 20th-minute strike.

Elsewhere Independiente thrashed ten-man Huracan 5-1. Goalkeeper Gaston Monzon was red carded after 58 minutes, with Facundo Parra, Nestor Silvera, Patricio Rodriguez (two) and Leonel Nunez rendering Javier Campora's 78th-minute penalty academic.

Third-placed Godoy Cruz were 1-0 winners over All Boys, Nicolas Sanchez scoring the winner. Gimnasia La Plata gave away a two-goal lead to draw away at Boca Juniors, for whom Cristian Cellay scored twice. Claudio Graf and Guillermo Barros Schelotto had given Gimnasia a 2-0 advantage after only 12 minutes.