Oribe Peralta struck an injury-time winner as America prevailed 3-2 over Morelia to make it five victories from five in Liga MX.
Mexico international Peralta fired the ball beyond onrushing Morelia goalkeeper Felipe Rodriguez in the second minute of added time to preserve America's perfect start to the Apertura season at the Estadio Azteca.
An unmarked Pablo Aguilar opened the scoring for America in the 38th minute with a close-range header.
Duvier Riascos levelled proceedings seven minutes into the second half courtesy of a header that hit the post and came off Moises Munoz's leg in goal.
Scores were level for just five minutes after America's Rubens Sambueza drove into space and unleashed a powerful shot from outside the penalty area.
Substitute David Depetris poked the ball home inside the six-yard box to restore parity in the 76th minute.
However, Peralta's 93rd-minute goal - his third in as many games - earned America maximum points against its lowly opponent, which sits second-bottom.
America's run of five consecutive wins has it two points clear of Atlas atop the table.
Atlas was a 1-0 victor over cellar-dweller Universidad Guadalajara thanks to Luis Cabellero's 90th-minute penalty.
New recruit and the league's top goalscorer Dorlan Pabon netted a hat-trick as third-placed Monterrey returned to the winner's list, toppling Cruz Azul 3-1.
Pabon, who joined from Brazilian outfit Sao Paulo at the start of the season, completed his treble with two goals in the final 17 minutes, as Monterrey ended its two-game winless streak.
Monterrey is level on 10 points with Queretaro, which played out a goalless draw at home to Veracruz.
In other results, defending champion Leon came from behind to beat Pumas UNAM 2-1.
Pablo Velazquez scored twice as Toluca accounted for Pachuca 3-0 at the Estadio Nemesio Diez.
Paulo da Silva was also on target for the home side, which now sits fifth in the table.
Tijuana ended a run of back-to-back draws after it edged Chiapas 2-1 courtesy of Dario Benedetto's double.
Carlos Quintero struck two minutes from time as Santo Laguna upstaged Guadalajara 1-0, while Puebla and Tigres UANL drew 1-1.