Leon moved closer to its first Mexican title in 21 years by beating defending champion Club America 2-0 in the first leg of the Apertura tournament final Thursday.
Carlos Pena opened the scoring with an opportunistic goal past the America goalkeeper barely 11 minutes into the match and Argentine striker Mauro Boselli added another in the 76th minute with a shot from an improbable angle.
Club America is playing for its 12th league title and a chance to become Mexico's most successful club after toppling Toluca 2-0 in the Apertura semifinals Sunday, while Leon drew 2-2 against Santos Laguna to win 5-3 over the two legs.
Mexico City team America is currently tied with Guadalajara rival Chivas on 11 league titles, while Leon, which was promoted to the first division in 2012, hasn't won a championship since 1992.
The return leg is scheduled to be played in Estadio Azteca next Sunday.
The Associated Press contributed to this report.