Javier Hernandez and Giovani dos Santos both scored twice as defending champions Mexico routed Cuba 5-0 in the Gold Cup on Thursday to become the first team to reach the quarter-finals.
The win, Mexico's second 5-0 rout in a row, came hours after the news that five of their players in the squad had tested positive for the banned substance clenbuterol in tests carried out on May 21.
Decio de Maria, general secretary of the Mexican Football Federation, named the players as Guillermo Ochoa, Francisco Rodriguez, Edgar Duenas, Antonio Naelson 'Sinha' and Christian Bermudez and said they had been suspended from the tournament.
Hernandez gave Mexico a 1-0 lead with a header in the 35th minute at the Bank of America stadium and three goals in five minutes just past the hour, two from Dos Santos, put the match beyond doubt.
Hernandez, who scored a hat-trick against El Salvador, volleyed home Mexico's fifth in the 75th minute to take his tally to five for the tournament.
Aldo De Nigris scored Mexico's other goal shortly after coming on as a substitute.
In an earlier Group A match, Randall Brenes scored in the closing seconds of injury time to lift Costa Rica to a 1-1 draw with El Salvador.
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