A man who was swept off rocks at Hill 60 was fishing on the rock platform without a life jacket.
A member of the public called triple-0 shortly after 4pm on Sunday afternoon, after seeing the fisherman get washed off the rocks.
Lifesavers from Port Kembla took out an inflatable rescue boat to retrieve the man from the water.
The man had no life jacket and was struggling to stay afloat.
Surf Life Saving NSW chief executive officer Steven Pearce said the outcome could have been a lot worse, had the lifesavers not been around.
"It's extremely disappointing that other members of the public haven't realised the dangers after the tragic loss of three men [on Friday]," Mr Pearce said.
Mr Pearce said anyone who fished or ventured onto rock platforms needed to wear a life jacket to give themselves a chance of survival - and out of respect to the three men who died on Friday and their families.
He acknowledged the person who called emergency services after seeing the fisherman get into trouble, saying it was the best thing to do.
"I really want to thank that member of the public for ringing triple-0," Mr Pearce said.
The rescue at Port Kembla was one of a number lifesavers conducted in the Illawarra on Sunday.
Multiple people were rescued from a rip after they swam outside the flags at Bulli in the morning, while a young woman almost drowned at Coalcliff when she too got caught in a rip.
A person was taken to hospital when they started experiencing anaphylactic shock after a bluebottle sting at Bellambi Beach, and another person suffered a dislocated shoulder at Coledale Beach.
Mr Pearce said the Illawarra's beaches were "packed" on Sunday, but it was pleasing to see that a lot of visitors were well-behaved and swam between the red and yellow flags.
The incidents at Coalcliff and Bulli, he said, reiterated the importance of staying between the flags when swimming.
In total, lifesavers conducted about 120 rescues in NSW on Sunday.
A man who was swept off rocks near Hill 60 at Port Kembla on Sunday afternoon has been taken to hospital.
The man was transported to Wollongong Hospital with possible minor injuries after surf life savers rescued him from the water.
He was washed into the water at the same location where three men died on Friday night.
A man has been washed off a rock platform near Hill 60 in Port Kembla on Sunday afternoon - where three people lost their lives less than 48 hours before.
Surf life savers have pulled the man from the water and administered oxygen.
On Friday night, two men in their forties - both from the same family - and a 69-year-old man died when they were swept off rocks near Hill 60.
Surf Life Saving NSW said on Saturday that life savers had responded to a "significant" number of call-outs and rescues, many of them the result of someone jumping or being swept off rocks.
NSW saw five coastal deaths within six days.
A strong marine wind warning is also in place for the Illawarra, and will stay in place until Monday, at least.
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