Two goals by Jon Dahl Tomasson earned Denmark a 2-1 victory over Uruguay in Ulsan, South Korea, Saturday and left the South Americans on the brink of elimination from the World Cup.
Coach Victor Pua's team, which looked dangerous at times but not consistently so, now must defeat world champion France in Busan on Thursday, or at least earn a tie, to stay alive in the 32-nation tournament.
If Uruguay does win, it will almost surely spell the end for France, which already has lost to Senegal in Group A play.
Further complicating matters for the French is that Coach Roger Lemerre said it would be "astonishing" if playmaker Zinedine Zidane could recover from a thigh injury in time to play in Thursday's match.
Saturday's game was entertaining and well handled by referee Saad Mane of Kuwait in front of a crowd of 30,157.
The Danes took the lead in the final minute of the first half after an excellent passing exchange left Tomasson free to side-foot the ball powerfully past goalkeeper Fabian Carini from close range.
Uruguay tied it two minutes into the second half on a superb left-foot volley from 20 yards by Dario Rodriguez, but Tomasson got behind the South Americans' defense again with seven minutes to play and headed in the winner off the underside of the crossbar.
"The first game is always a nervous affair and it's psychologically difficult," Denmark Coach Morten Olsen said. "I thought that after the first 25 minutes we controlled the game physically, tactically and technically."