Mexico scraped out a 1-0 victory over Jamaica in their Group B opener in the Copa America in Houston, but their winning start was tempered by what appeared to be a potentially tournament-ending injury to captain Edson Alvarez.
Alvarez, who plays for West Ham United in England and is one of the most experienced players on the Mexican team, collapsed clutching his hamstring in the 30th minute and limped off the pitch in tears.
Jamaica, who are ranked 38 places below Mexico, thought they had scored their first-ever Copa America goal when Michail Antonio headed into the net five minutes into the second half, but the goal was ruled out for offside by the video assistant.
Mexico stepped up a gear after that scare, with Luis Chavez, Santiago Gimenez and Gerardo Arteaga all drawing fine saves from Jamaica keeper Jahmali Waite, before Arteaga finally broke the deadlock in the 69th minute with a thunderous strike.
Mexico, who are making their 11th appearance in the Copa America, reached the final in 1993 and 2001.
Both teams had relatively inexperienced goalkeepers. Julian Gonzalez made his third start for Mexico after veteran Guillermo Ochoa was dropped from the squad and his predecessor Luis Malagon was injured recently.
Waite got the nod for Jamaica because Andre Blake, a two-time Major League Soccer Goalkeeper of the Year for the Philadelphia Union, was injured before the tournament. Waite made eight saves.
The result moved Mexico level on three points with Venezuela, who beat Ecuador 2-1 in the other Group B clash earlier in the day.
Jamaica play Ecuador in Las Vegas on Wednesday, while Mexico faces Venezuela in Inglewood, California.