However, The Daily Telegraph has reported that the NRL were not concerned by the incident because Williams was wearing a mask and was duly seperated from the fan by a fence.
"There is no issue.
"Like all returned travellers, Sonny Bill and his family are going into mandatory hotel quarantine for 14 days," an NRL spokesperson told News Corp.
The organisation also pointed out that Williams' mandatory 14-day quarantine period would safeguard him from any risk, though they apparently failed to mention the wellbeing of the Roosters fan.
After being bustled through the airport, Williams and his family were taken to the luxurious Meriton Suites Pitt Street in the Sydney CBD, where they will now stay in a three bedroom penthouse that has views of the Sydney Tower as well as the city's glamorous harbour.
Roosters coach Trent Robinson says Williams has a training regime and will get the help of the club's strength and conditioning team to get up to scratch when he joins the team in two weeks.