"Sydney" was proceeding on a south-south-east bearing, apparently not under control. The Australian warship quickly disappeared from German sight, although the glow of the burning ship consistently lit the horizon until 22:00, with some German survivors stating that the light was visible consistently or occasionally until midnight. "Sydney" sank during the night; it was originally thought that the cruiser exploded when fires reached the shell magazines or torpedo launchers, or took on water through the shellholes on her port side and capsized. However, after the wrecks were located, it was determined that "Sydney" was under limited control after the battle, maintaining a course of 130–140 degrees true at speeds of . The ship remained afloat for up to four hours before the bow tore off and dropped almost vertically under the weight of the anchors and chains. The rest of the ship sank shortly afterward, and glided upright for underwater until it hit the seabed stern-first.