Nearby, Burwood Tennis Club members were playing their club championship.
President James Kirner heard Ms Clark's cries for help and with seven other players rushed to help. They pulled the attacking dog off Charlie and then formed a circle to keep it from getting at him again.
"The staffy kept coming back for more. The rottweiler also started coming toward us and ran around the circle, trying to get Charlie. He might have got a few taps from the tennis rackets but we had to get them away," said Mr Kirner.
Mr Kirner said owner of the staffy tried to hold onto the rottweiler and his other dog.
"He didn't really do much. He clearly couldn't handle his dogs," he said.
The tennis players carried Ms Clark and Charlie back to the clubrooms and waited for city council animal control, police and an ambulance to arrive.
"We could see she was in trouble and we were all only too happy to help. It was lucky we were there because on a Sunday we never are. We dived in and helped. Pip's a brave wee cookie. A lot of people just would have left their dog there and taken off but she didn't," said Mr Kirner.
"They are my heroes. They came to my rescue. I didn't think anyone would come to help me. I think Charlie would have been killed and I probably would have ended up in hospital," said Ms Clark.
"The dogs were like a pack, they all wanted to have a go at Charlie. It was so scary. I am still in shock from it. I am not sure if I want to to walk my three dogs, Pepe, Jack and Charlie, at the park again.''
City Council Acting Inspections and Enforcement Unit manager Anne Columbus said the owner had voluntarily had the staffordshire bull terrier euthanised.
A decision has not yet been made as to whether any charges will be laid against the owner.