Shubman Gill stars with bat as India sink England in ODI opener
Shubman Gill led India to a commanding four-wicket win over England in the opening ODI on Thursday following a stellar bowling display from the hosts in Nagpur.
Cummins opted to miss the ongoing Test series in Sri Lanka to be present for the birth of his second child, though he is also dealing with an ankle issue.
The Champions Trophy, which will be held in Pakistan and the UAE, kicks off on February 19.
"Pat is very unlikely to make it, which is disappointing, and we're also dealing with Josh Hazlewood, who's currently struggling as well," coach Andrew McDonald said during an interview with radio station SEN. "We'll get the latest medical updates in the coming days, and that will give us a clearer picture so we can inform everyone on the next steps."
With Cummins absent, the Australians will need to find a replacement captain for the ODI tournament.
Vice-captain Mitchell Marsh, who leads Australia in T20Is, has already been ruled out of the eight-nation competition due to a back injury.
Steve Smith has been captaining the Test team in Sri Lanka.
"Pat Cummins hasn't been able to resume bowling, so he's extremely unlikely to play," McDonald explained. "This means we do need to appoint a captain. We've been having discussions with Steve Smith and Travis Head as part of our Champions Trophy preparations, alongside Pat back home. They'll be the two leading candidates for the captaincy."
Hazlewood's participation in the recent series against India was limited to just two Tests due to calf and side injuries.