Elias Mokwana played in the second half but not even his presence could save Esperance from a 2-0 loss against Flamengo in Group D's fixture played at the Lincoln Financial Field in Philadelphia.
The South Americans looked set to dominate proceedings from the first whistle as the North Africans were reduced to chasing shadows in the early exchanges.
A good move in the 17th minute ended with Luis Araujo setting up Giorgian de Arrascaeta for an easy finish.
South Africa international Elias Mokwana got his chance after the break when he was introduced alongside Abdramane Konate, with Esperance hoping to turn the tables.
However, it was Flamengo who got their second in the 70th minute when former Arsenal midfielder Jorginho teed up Pedro for their team's second goal.
Esperance and Los Angeles are now at the bottom of their pool with no point after initial losses.