M-Z450-mounted Arco beat arch rival and Buenos Aires local and circuit expert Demin Villar to the crown in front of a packed-to-capacity crowd after a season-long tooth-and-nail battle with the Honda rider.

Arco, who entered the series finale with a 14-point lead, rode a tactical race and finished fourth overall on the day; enough to give him and Suzuki Argentina the coveted MX del Norte 2012 crown after 10 races.

He said: "Many win races; only one wins a championship. I'm really happy and moved to win the title and I have an incredible team of people behind me to thank; Suzuki Argentina, all my sponsors, my family, friends and fans who always support me."