The Daily Mail says Newcastle are anxiously awaiting the results of tests amid fears Hayden suffered a season-ending knee injury at Brighton.
Hayden was left in clear pain and carried off on a stretcher following lengthy treatment on the pitch after an accidental collision with Seagulls midfielder Yves Bissouma.
Midfielder Hayden, 26 on Monday, underwent scans on Sunday to determine the seriousness of the suspected knee ligament injury.
Manager Steve Bruce said following his side's 3-0 defeat at The Amex Stadium: "It's a knee injury. We don't know the severity until obviously he has scans and x-rays but it doesn't look too good that's for sure."
A significant lay-off is expected which would be a major blow to Newcastle as they battle to avoid relegation with just nine games left to go.
Need a VPN? Or seeking to switch? Then support Tribal Football by clicking here to sign up with our official partners NordVPN. Not only will you receive the best VPN experience, but also great discounts by signing up via Tribal Football. Thanks for your support!