Manuela Vanegas headed a stoppage-time winner to give Colombia a 2-1 upset victory over Germany just when the twice world champions thought they had saved a point in a thrilling Women's World Cup clash at Sydney Football Stadium on Sunday.

The defender powered the ball home from a corner eight minutes after German striker Alexandra Popp had converted a penalty to cancel out a stunning strike from Colombian teenager Linda Caicedo.

Caicedo, who gave her team a fright by collapsing in training on Thursday, had delighted the massed ranks of her compatriots in the 40 499 crowd with a goal of the highest quality in the 52nd minute.

The Colombians tore into the match from the kickoff and the Germans looked rattled not only by their aggression but also by the deafening noise of their yellow-shirted fans.

Colombia striker Mayra Ramirez headed a chance down and wide in the ninth minute and the South Americans continued to niggle the Germans with a dig to the ribs here and a flailing arm in the tackle there.

The corner was Germany's major weapon in their opening 6-0 thrashing of Morocco but Colombia goalkeeper Catalina Perez came out confidently to gather the first ball swung in from the corner flag.

Germany forward Lina Magull had a good chance in the 21st minute but her swing at the ball made contact with nothing but air and Lena Oberdorf's subsequent effort was blocked.

Popp, who scored two goals against the Moroccans, should have added to her tournament tally in the 42nd minute but blazed her volley high and wide from close range.

Colombia continued to launch the ball forward to their front players at every opportunity but it was not until seven minutes after the break that they were able to break the stalemate.

Showing no sign of the nerves that her coach said were behind her collapse on Thursday, the 18-year-old Caicedo gathered the ball on the left edge of the box, cut back between two defenders and curled it into the top right-hand corner.

The stadium exploded with noise as the diminutive teenager celebrated her second goal at the tournament, having become the youngest player to score in this World Cup with a similar effort in the 2-0 opening win over South Korea.

Germany continued to spurn what chances they created but, with two minutes left on the clock, Oberdorf was brought down in the box by Perez and Popp stepped up to thump the ball confidently into the net.

The 27th-ranked Colombians now need only a draw against Morocco in their final Group H match to be certain of reaching the last 16, while Germany are still likely to progress if they beat South Korea in their last fixture.