Newell's Old Boys moved three points clear at the top of the Argentinian Clausura standings on Saturday night with a 3-1 home win over Union Santa Fe.
First-half goals from Victor Figueroa, Santiago Vergini and Maximiliano Urruti put the hosts in the driving seat, with Matias Donnet's 58th-minute strike proving little more than consolation for the visitors, whose misery was compounded by the late dismissal of Juan Avendano.
The triumph gave Newell's a three-point cushion at the summit over Boca Juniors, who face Velez Sarsfield on Sunday night, and Arsenal, who won 4-1 at San Martin San Juan on Friday.
All Boys consolidated fifth spot, and remained four points behind Newell's, thanks to a convincing 3-0 victory at Independiente. Martin Morel, Matias Rudler and Mauro Matos were the men on target.
Bottom-of-the-table Olimpo picked up only their eighth point in 14 games in a 1-1 draw at San Lorenzo - and Nestor Bareiro's second-half strike would have earned all three points had Emmanuel Gigliotti not snatched a last-gasp equaliser for San Lorenzo in a frenetic finale which also saw Olimpo midfielder Damian Musto sent off.
There was also late action at Belgrano Cordoba, where Alexis Castro's 89th-minute goal secured Atletico Rafaela a 1-1 draw after Claudio Perez's fifth-minute penalty had put the home team ahead.