Also on Wednesday, fellow Brazilians Corinthians got their title defence back on track with a resounding 3-0 home win over Tijuana in front of a 33,000 crowd at the Pacaembu in Sao Paulo, having had to play their previous home match behind closed doors.
An own goal by The Strongest's Luis Mendez, under pressure from Serginho, eight minutes from time gave Atletico a maximum 12 points at the top of Group Three, eight more than second-placed Sao Paulo, who visit Argentina's Arsenal on Thursday.
Striker Diego Tardelli gave Atletico the lead in the ninth minute but Harold Reina equalised before half-time for the Bolivian side.
Reina tapped in the loose ball after goalkeeper Victor was deceived by its bounce in the rarefied atmosphere at the Hernando Siles 3,600 metres above sea level.
Club World Cup winners Corinthians had their supporters banned from all their matches for two months after a firework launched by one of their fans at their opening Group Five match away to Bolivia's San Jose killed a teenager in the home crowd in Oruro on February 20.
South American governing body Conmebol lifted the ban on fans at the Pacaembu but has maintained and extended to 18 months a suspension on travelling Corinthians supporters.
The team carried a banner on to the pitch that read "The Pacaembu is more beautiful with you" to thank their fans for their support.
They then proceeded to dismantle the Mexican champions, who had beaten them 1-0 in Tijuana last week, with goals from Pato, Paolo Guerrero and Paulinho.
Tijuana lead the group with nine points from four matches, two points more than second-placed Corinthians.
Three-times winners Olimpia crushed Venezuelan newcomers CD Lara 5-1 away in Barquisimeto. The Paraguayan side are top of a tight Group Seven, one point ahead of Argentina's Newell's Old Boys and Universidad de Chile.