Uruguay came from behind to open their Olympic football campaign with a narrow victory over an impressive UAE.
Ismaeil Matar gave the Asian side a deserved lead with a composed finish, while Martin Campana made several saves for an out-of-sorts Uruguay.
Gaston Ramirez levelled with a free-kick close to the break before substitute Nicolas Lodeiro struck the winner.
Ahmed Khalil had a chance to level for UAE but dragged his effort wide.
Nonetheless, his team were clapped off the pitch after a spirited and skilful performance that showed they aim to do more than simply make up the numbers in Group A.
Uruguay's two Olympic gold medals came at the football competitions in 1924 and 1928 and, having qualified for the first time in 84 years, they went into the 2012 tournament as one of the favourites.
But on a day when another heavily fancied team in
Spain were defeated by Japan,
La Celeste were clearly rattled by their opponents and they endured a far from straightforward return to the Games.
Liverpool forward and Uruguay skipper Luis Suarez, last season
found guilty of racially abusing Manchester United's Patrice Evra,
was booed by sections of the Old Trafford crowd every time he touched the ball, while the UAE really took the game to their opponents.
UAE had a penalty appeal turned down when Sebastian Coates tangled with the impressive Omar Abdulrahman before Ismaeil Matar scored - latching on to a through ball from Abdulrahman and evading Campana before placing his strike into the bottom corner.
The Asian side continued to press and Khalil had a shot smothered by the keeper, who also denied Rashed Eisa after he tore down the left and into the Uruguay box with almost embarrassing ease.
The South American side were in disarray, lacking cohesion in attack and starting to show signs of discontent. Their neat, intricate passing moves were breaking down and it was no surprise when their equaliser came from a free-kick.
Edinson Cavani had already struck one over the crossbar but Bologna's Ramirez made no mistake shortly before the interval with a strike from 25 yards.
Uruguay coach Oscar Tabarez brought on Lodeiro at the break and it proved to be a shrewd decision as he smashed the ball home from a tight angle after an assist from Suarez.
Ali Khaseif had already made an acrobatic finger-tip save shortly after the restart to tip over Egidio Arevalo's thunderous effort but he was powerless against Lodeiro's low first-time strike.
Uruguay had finally assumed a measure of control but UAE did create one final chance when Abdulrahman played an inch-perfect through ball to Khalil, who could not find the target with his first-time strike.