Ronaldo scored one of Corinthian's two late goals in a 2-0 win at Ituano on Sunday to keep the club in semifinal contention in the Sao Paulo state championship in Brazil.
In other Brazilian matches, Robinho returned from injury to score for Santos in the Sao Paulo tournament, while Flamengo, Botafogo, Fluminense and Vasco reached the semifinals of the Rio Cup, the second stage of the Rio de Janeiro state championship.
Former Real Madrid striker Ronaldo tapped Corinthian's second goal into an empty net after a cross from Tcheco in the 86th minute against Ituano, adding to Jucilei's opener five minutes earlier.
The win pushed Corinthians into fifth place with 32 points, one behind Sao Paulo and two behind third-place Gremio Prudente, with one match left to decide the semifinal line-up.
Santos remained atop the Sao Paulo tournament as Robinho scored the third goal in a 3-1 win over Sao Caetano, while second-place Santo Andre, also sure of a semifinal spot, played to a 1-1 draw at Rio Claro on Saturday.
In the Rio Cup, Dodo scored a 78th-minute winner as Vasco beat Duque de Caxias 4-3 to join Group B winner Botafogo in the semis. Botafogo had a 2-2 draw with Bangu.
Defending Rio champion Flamengo won 3-0 over Friburguense to top Group A, and will be joined in the semifinals by Fluminense, which secured second after a 3-1 win against Macae.
In the Rio Grande do Sul state tournament, Gremio extended its winning streak to 15 games with a 2-1 win over Juventude.
In Argentina, Godoy Cruz stayed three points behind Independiente atop the Clausura standings after Rodrigo Salinas and Cesar Carranza scored second-half goals in a 2-0 home win against Velez Sarsfield.
Boca Juniors and River Plate both lost, while Estudiantes La Plata drew 1-1 with defending champion Banfield.
Boca's season deteriorated after going down 2-1 at home against Rosario Central, leaving the Buenos Aires giant third from last in the standings.
Milton Caraglio headed the winner for Central in the 86th minute, breaking the deadlock after Boca's Nicolas Gaitan had canceled out Adrian De Leon's first-half opener.
Juan Roman Riquelme was sent off for protesting against refree Rafael Furchi's decision to award a free kick that led to Central's winning goal.
River Plate is just a point better off than Boca after a 1-0 defeat at Lanus left the club in 16th position. Sebastian Blanco scored the winner for Lanus in the 41st minute.
Estudiantes lost ground at the top after Marcelo Quinteros scored the equalizer for Banfield in the 41st minute.
Estudiantes had to hold on for a point after Enzo Perez was sent off in the 70th minute.
Independiente leads the standings with 27 points, followed by Godoy Cruz on 24, Argentinos Juniors on 22 and Estudiantes on 21.
In a clash between Mexico's two biggest clubs, Omar Arellano scored the winner to give Chivas a 1-0 win over America.
The win pushed Group 1 leader Chivas back to the top of the general standings, ahead of Group 2 leader Monterrey, which had a 1-0 win over Pumas on Saturday.
Toluca thrashed Estudiantes Tecos 5-0, while Jaguares claimed a 3-0 away win at Group 3 leader Santos in Sunday's other matches.