Tocalli becomes Argentine season's 9th coaching casualty
"We didn't win the title or qualify for the Libertadores Cup, which were the targets, and that was the cause of my not carrying on," the former Argentina under-20 coach told reporters.
"But we are sixth in the table and we have a good squad."
Former South American champions Velez, considered one of Argentina's top clubs after River Plate and Boca Juniors, have taken 26 points from 17 games in the Apertura championship and have two matches left to play.
"They told me they didn't intend to renew my contract. For me, there was no point in being in charge for these last two games," he said.
Tocalli, who had not previously coached a first division side, had been in charge since January.
Two coaches have lost their jobs at Huracan during the course of the championship and there have also been changes at River Plate, Independiente, Rosario Central, Gimnasia-La Plata, Estudiantes and Godoy Cruz. (Reporting by Brian Homewood; Editing by Peter Rutherford)