Messi, edging closer to fitness with the tournament starting Thursday and Argentina's first match looming on June 16, began on the substitutes' bench against Iceland in Alabama.The legendary attacker, now 38, drove Argentina to their third World Cup crown in Qatar four years ago and is feeling his way back after injuring a hamstring playing for Inter Miami in late May.Messi has not featured so far in his country's build-up games but could make an appearance in the Iceland friendly.Dream ripped awayThe biggest-ever World Cup, taking place in the United States, Canada and Mexico, has been dogged in the lead-up by numerous controversies.Somali referee Omar Artan said the "biggest dream of my life" had been ripped away after he was turned back at the US border and then dropped from FIFA's list of referees for the competition."I am very, very disappointed," Artan told The New York Times from Istanbul, where he returned after being refused entry in Miami."I'm just simply a referee who's trying to live his dream, the biggest dream of my life, to come to the World Cup."Artan said he was subjected to an 11-hour interview with border officials at Miami International Airport and then taken to a holding cell where he was detained for several further hours before being put on a flight back to Turkey."I had the right papers and everything. I had the right visa," he added -- an assertion confirmed to AFP by a Somali government advisor.Mexico City protestsConcerns were rising that the opening match of the World Cup in Mexico City on Thursday could be disrupted by social unrest.