Brazil's Cruzeiro maintained its 100 per cent record in this season's Copa Libertadores group seven with a 4-0 home win over Guarani of Paraguay on Tuesday.Striker Wallyson scored in the 30th and 74th minutes for the two-time Libertadores champion Cruzeiro, with late goals from Ernesto Farias and Thiago Ribeiro sealing the win.Cruzeiro lead Group Seven with six points, three ahead of Deportes Tolima of Colombia. Tolima travels to Argentine champions Estudiantes, who Cruzeiro beat 5-0 in their group opener, on Wednesday.The brace from Wallyson made him the group stage's leading scorer with four goals.Wallyson volleyed in his first after the Guarani defence failed to clear a corner and scored his second from close in after Walter Montillo's left-wing cross in the second half.Farias finished a pass from Dudu for Cruzeiro's third goal in the 87th and Thiago Ribeiro hit a long-range shot to complete the scoreline just before the final whistle.Meanwhile, a 34th minute header from a corner by Eduardo Morante gave Ecuador's Emelec a 1-0 win over Jorge Wilstermann of Bolivia in Group Six.Emelec leads the group with four points.In Group 1, Gianfranco Labarthe gave Peru's San Martin the breakthrough in the 85th minute against San Luis of Mexico, with Carlos Marinelli adding a second in stoppage time.In the same group, Dayro Moreno scored in the 29th minute as 2004 champion Once Caldas of Colombia took the lead against Libertad of Paraguay.Moreno's strike looked to have earned all three points until substitute Victor Ayala hit a low shot from 25 yards to equalise with the last kick of the match.San Martin lead the group with six points, two clear of Libertad, with Once Caldas on one point and San Luis bottom on zero.