Universidad de Chile also qualified as Group Eight winners with one match to spare thanks to Santiago rivals Universidad Catolica's 2-0 home win over Brazilian champions Flamengo.
Goals from Dentinho and Elias gave Corinthians the win over modest Racing in Montevideo that put them six points clear of their second-placed Uruguayan rivals with one match to go in Group One.
The Brazilian side have 13 points, Racing seven, Colombian champions Independiente Medellin six and Cerro Porteno of Paraguay one.
Striker Dentinho, so called because of his toothy grin, put Corinthians in front when he netted an attempted clearance of Roberto Carlos's hard, low cross from the left midway through the first half. Elias headed the second three minutes from time.
In Group Eight, Universidad de Chile, who beat Caracas FC 3-1 on Tuesday, were indebted to fellow Chileans Catolica.
Catolica who scored first half goals through Argentine Damian Diaz after two minutes and fellow midfielder Francisco Silva on the stroke of half time.
"The U" have 11 points, Flamengo seven, Catolica six and Caracas two. Flamengo will need a good win over Caracas next week to try to qualify as one of the best six second-placed teams from the eight groups.
In Group Five, Ecuador's Emelec made life difficult for another Brazilian team by holding Internacional 0-0 at home in Guayaquil, preventing them from overtaking leaders Deportivo Quito. Inter's Kleber was sent off in the 73rd minute.
Deportivo have 10 points from five matches to Inter's nine with Cerro of Uruguay on seven and Emelec one. All hinges on next week's final matches in the group when Inter host Deportivo and Cerro are at home to Emelec.
