Uriel Antuna scored a hat trick as Mexico got their Gold Cup campaign off to a dominant start with a 7-0 rout of Cuba in their opener at the Rose Bowl on Saturday.
The 21-year-old was a last-minute replacement for injured defender Jorge Sanchez in the Mexico squad for the tournament and the addition paid big dividends.
The LA Galaxy midfielder, on loan from Manchester City, gave Mexico the perfect start in their quest for a seventh Gold Cup title when he scored in the second minute of the match, moments after Raul Jimenez had hit the post from close-range.
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Antuna, who just made his international debut 10 days ago off the bench against Venezuela, gave his team a 4-0 advantage in the 44th minute, then capped his night with a final goal in the 80th minute.
Wolverhampton Wanders star Jimenez scored twice, while Diego Reyes and Ernesto Vega also tallied for El Tri.
Cheered on by a supportive crowd, Mexico showed no sign of letting down their fans down despite missing key figures like Hector Herrera, Javier "Chicharito" Hernandez, Carlos Vela and Hirving Lozano from their squad.
It was a first competitive win for new manager Gerardo "Tata" Martino, who was hired back in January and had overseen three friendly wins against South American opposition.
"I was surprised I was going to get the start," Antuna told Univision after the match. "But I just took advantage of the situation, [Martino] showed great confidence in me."
Cuba, making their first Gold Cup appearance since 2015, have now lost to Mexico four times in as many meetings in the biennial championship of the North, Central American and Caribbean region.
"We had a great match, we took the initiative from the beginning," Jimenez told Univision after the match. "The first goal helped us, it opened up with the match."
Canada earlier thrashed Martinique 4-0 at the same stadium in Saturday's other Group A match.
Information from Reuters was used in this report.