San Martin stuns Arsenal

Having started with five straight losses, San Martin kickstarted its campaign thanks to goals from Emmanuel Mas, Mauro Bogado (penalty), Humberto Osorio and Jorge Luna (penalty).

The visitor's misery was compounded by a red card in either half - the first for Lisandro Lopez and the second for Diego Braghieri.

Colon Santa Fe enjoyed a much more productive first five games than San Martin and could have joined Boca Juniors at the summit if it had picked up just a point at San Lorenzo, but they went down 2-1 - its first loss in six games this term.

Julio Buffarini and Denis Stracqualursi put the host in the driving seat and the visitor suffered a further setback when Sebastian Prediger was sent off 16 minutes from time.

Gerardo Alcoba nevertheless halved the deficit in the 89th minute but it was too little, too late.

Velez Sarsfield also had the chance to take over at the top, but was held to a 0-0 draw at Estudiantes and had defender Juan Sills sent off just before the end.

Finally, Atletico Rafaela registered its first win of the season with a 2-1 home success against All Boys. Juan Eluchans and Sebastian Grazzini were the men on target for Atletico in the first half, with Mauro Matos grabbing an 84th-minute consolation for All Boys.