The United States women's team came back from two goals down to beat France 4-2 in their opening Group G game.
The defending gold medallists were up against it after neat finishes from Gaetane Thiney and Marie-Laure Delie put France in charge after 14 minutes.
But goals from Abby Wambach and Alex Morgan levelled matters before Carli Lloyd and a second Morgan goal settled the game in the American's favour.
In the other Group G game, North Korea beat Colombia 2-0.
The second match at Hampden Park was delayed for over an hour after the North Korea team walked off the pitch in protest at their images being mistakenly shown on a screen beside a South Korean flag.
When the game finally got under way, the North Koreans took victory thanks to a goal in each half from Song Hui Kim.
As expected, tournament favourites United States got off to a winning start, but they were made to work hard by a French side whose confidence was fuelled by a 17-match winning streak coming into the Games.
They demonstrated their form by racing into a 2-0 lead through Thiney's long-range effort into the top corner and Delie's finish following a scramble from a corner.
However, the US rallied and were level just after the half-hour mark when Wambach headed home from a corner before Morgan chipped in over French goalkeeper Sarah Bouhaddi.
Lloyd blasted the Americans into the lead and Morgan made sure of the win with her second goal - a neat, close-range finish from Tobin Heath's cross.