Play was delayed on the outside courts at the Australian Open on Thursday because of the dust and mud that came down during a rainstorm in Melbourne on Wednesday night.
The courts had to be power-washed with organisers saying the start would be delayed by three hours on most of them.
Play eventually began on courts three and 19 but rain then forced a suspension until nearly 04:00 GMT.
After the rain stopped, five courts had still not started by 05:00.
Matches began as scheduled at 00:00 on the three courts with a roof.