Victoria Police attended the Pullman Hotel in East Melbourne on Monday and said they were investigating a report of sexual assault in the early hours of the morning.
Swans chief executive Matthew Pavlich on Monday afternoon confirmed some of the club's players had been involved in an "alleged incident" but refused to say whether any had been arrested.
The Swans stayed at the hotel on Sunday night after their 36-point win over Essendon at the MCG. That victory locked in second place on the AFL ladder and a home qualifying final.
On Monday afternoon, Pavlich addressed the media in Sydney.
"We can confirm that several players were involved in an alleged incident last night in Melbourne," he said.
"We've identified this to the AFL that we are working with them and also the relevant authorities on this matter.
"We're still piecing together exactly what's transpired here and have our own set of internal inquiries ongoing.
"But safe to say that we're extremely shocked and disappointed that this has taken place and that the players have found themselves in this situation.
"We understand the level of interest in the matter and there'd be lots of speculation, but given it's a police matter right now, that is all that we can say."
Pavlich was then asked whether anyone had been arrested.
"As I said, it's a police matter ongoing. I'm not going to comment any further on it right now," he said.
Police had earlier confirmed they were investigating a report of sexual assault.
"Police are investigating a report of a sexual assault in East Melbourne on 17 August," Victoria Police said in a statement provided to AAP.
"The incident occurred at a hotel on Wellington Parade in the early hours of the morning.
"The exact circumstances are yet to be established and the investigation into the incident remains ongoing."
The news has rocked premiership fancies Sydney as the Swans gear up for an AFL finals campaign.
The Swans play North Melbourne at the MCG on Sunday, then have a week off before a home qualifying final.
As of Monday afternoon, no players had been charged in regards to the investigation.
The Swans and the AFL will face a decision on whether to stand down the players allegedly involved.
Unlike the NRL, the AFL does not have a strict no-fault stand-down policy on players charged with offences such as sexual assault.
But the AFL stood down Geelong's Tanner Bruhn, who ultimately had sexual assault charges dropped, for the entire 2025 season while his case was in court.
Bruhn, who always maintained his innocence, returned to play this year.
AAP has contacted the AFL for comment.
1800 RESPECT (1800 737 732)
National Sexual Abuse and Redress Support Service 1800 211 028