A growing Covid-19 outbreak in Sydney's northern beaches region is being closely monitored by Cricket Australia as state governments move to tighten their borders across the nation and force early contingency planning around the SCG Test in the new year. David Warner, who is currently in Sydney continuing his recovery from the groin injury that ruled him out of the first Test, may be flown to Melbourne early to avoid any potential further border restrictions to Victoria.

Multiple Sydney-based members of the broadcast production teams in Adelaide were stood down as a precaution on Friday morning and the commentator Brett Lee flew home to Sydney, while CA issued a directive to all media covering the Test match to report if they had visited the northern beaches region in the past week.

By early evening, health orders had caused another change as the former Australian captain, ABC commentator and northern beaches resident Ian Chappell was compelled to go into self-isolation in his Adelaide hotel, due to SA Health's directive that all individuals who had spent time in "High Community Transmission Zones" since December 11 had to "self-quarantine immediately at a suitable location for 14 days" and submit to Covid-19 tests. Chappell had flown into Adelaide this week to work at the Test.

As a fellow northern beaches resident, Mitchell Starc would have run the risk of facing similar conditions and thus being forced out of the Test match, if not for the fact that he had gone into self-isolation on December 11 as part of CA's own Covid-safe protocols. The governing body sought clarification on Starc's status with SA Health before keeping him in the match on day two.

"Very early on there was but given the day/night times I was asleep when this was happening," Australia captain Tim Paine said when asked if there was any conjecture around Starc. "We went through the appropriate channels and everything was checked off and approved by the time I got up, about 10am today. I know our manager and coach were working very busily behind the scenes to get all the information."

The cluster, centred around Avalon beach to Sydney's north, is currently at 28 cases and counting, although New South Wales Health has successfully contact-traced all but one of these. The region north of the Spit Bridge is currently under stay-at-home orders, but the South Australian and Victorian borders - both critical to the continuing Test series between Australia and India - remain open to NSW. Victoria's state government has announced a permit system for NSW visitors to the south, while at the same time advising their own residents not to visit Sydney for the time being.

We started out thinking how to play the full series as safely as possible, and we'll take the same approach over the coming days and weeks. We've got contingency plans around a whole range of different options, and we've had to be agile all the way through. We were encouraged that it was 17 cases yesterday and ten today, and we'll see how that plays out over the next 72 hours
Nick Hockley

CA is understood to have remained in constant dialogue with the Melbourne Cricket Club around ensuring a pitch is ready for playing back-to-back Tests at the MCG in the event of Sydney's outbreak growing further. However, the governing body is adamant it will not make binding decisions too quickly, while also noting that the current situation in Sydney underlines the prudence of maintaining hub protocols around the India series and the concurrent BBL, which has matches scheduled to be played in Tasmania, Queensland, the ACT and South Australia over the next two weeks.

"There's been lots of discussion and meetings of our medical experts, but this is the reason why throughout the summer we've had our players in bubbles in the hub," CA's interim chief executive Nick Hockley told SEN Radio. "We're monitoring the situation; we're not panicking at all, staying calm. Adelaide, a few weeks ago we had that pizza-shop outbreak and through that process we worked very calmly to get the players in Adelaide on a charter plane, out of Adelaide within 24 hours and that really saved the summer.

"We've got the Sydney Test and the BBL in NSW after that, so the fact we're here in Adelaide, we've got the next Test in Melbourne, it's really watch, wait and see and I think the governments around the country have handled the pandemic so well, so we'll watch, learn and stay in touch."

Hockley dismissed notions that the SCG Test was in doubt, not at this stage. "I don't think so - this is the very reason why we have the hubs in place," he said. "It's been interesting as we've worked through to almost zero community transmission, we've had lots of questions about do we need the hubs. Over recent weeks they've not been about protecting people against coronavirus as much as getting tangled up. We knew there were going to be cases pop up, so not getting caught up in this web of people having to go into isolation.

"Whether it's the WBBL players, the BBL players, the BCCI, our own Australia squads, they have been absolutely fantastic in dealing with all the protocols. Our medical experts have been working around the clock, we're in very good communication with health authorities around the country. It's one of the things we've had to navigate with getting cricket up safely."

Should states close their borders, for instance from NSW to Queensland between the third and fourth Tests, Hockley said the matter would be handled on a case-by-case basis. "The fact all our players and support staff are in these hubs, we've got a very clear set of protocols," he said. "They are business continuity measures to make sure if there are situations and restrictions around borders that we can give ourselves the best chance to move around safely.

"If the game can be played safely [in Sydney] then we'll play it there. That's our starting point, so it's working with the health authorities to ascertain that. We started out thinking how to play the full series as safely as possible, and we'll take the same approach over the coming days and weeks. We've got contingency plans around a whole range of different options, and we've had to be agile all the way through. We were encouraged that it was 17 cases yesterday and ten today, and we'll see how that plays out over the next 72 hours."

Tickets for the SCG Test remained on sale as of Friday.

Daniel Brettig is an assistant editor at ESPNcricinfo. @danbrettig