NSW has breathed a sigh of relief as the state recorded zero new local COVID-19 cases on the first full day of reimposed restrictions.
Premier Gladys Berejiklian said on Friday she was "pleased" with the state's progress.
However, the link between an infected eastern Sydney man and an international traveller with the same COVID-19 strain remains unclear.
The man, in his 50s, duly infected his wife.
More than 13,000 people were tested in the 24 hours to 8pm on Thursday, with no additional cases recorded.
Restrictions for Greater Sydney were reimposed on Wednesday including mandatory masks in indoor settings and public transport, a 20-person cap on indoor gatherings and a ban on most singing and dancing.
A health alert was issued on Thursday evening for Haymarket restaurant XOPP, with diners present between 1.30pm and 2.30pm last Wednesday asked to seek testing and self-isolate until they have received a negative result.
The same advice was issued for Bondi Trattoria at Bondi Beach on April 29 and Fratelli Fresh in Sydney's CBD on April 27.
A number of places have also been listed as sites where fellow attendees are close contacts who must isolate for 14 days, including the exclusive Royal Sydney Golf Club, a CBD optometrist, and other venues in Paddington, Rushcutters Bay, Moore Park and Collaroy.
Other places - including a number of barbecue shops throughout Sydney - are lower-risk, with fellow visitors asked to isolate until they receive a negative result.
The missing epidemiological link between the infected man and the coronavirus-positive traveller in hotel quarantine remains unclear.
"The only concern for us is obviously the fact that at least one person has been in the community going about their business for a few days, having the virus and not knowing they have it ... it could be more than one," Ms Berejiklian told the Nine Network.
"We're just saying to people: go about your daily business, just be extra safe."
New Zealand called a time-out on the travel bubble with NSW on Thursday, suspending quarantine-free travel from the state for 48 hours from Friday.
Ms Berejiklian urged businesses to stay open and Sydneysiders to show up for their Mother's Day reservations on Sunday.
"Every time we go through this in NSW, we learn from what we experience, learn from what we did well or didn't do well, then we can apply it into the future," Ms Berejiklian said.
