The striker has enjoyed a scintillating start to the season after netting seven goals in nine appearances in all competitions.
But the Japanese star was seen clutching his right knee after going to ground with no one around him during the second half of Tuesday night’s 1-0 victory.
After receiving some treatment from medical staff, Furuhashi limped off the pitch unaided but has kept Hoops supporters in the dark over the severity of his injury scare.
Ange Postecoglou’s new £4.6m signing from Vissel Kobe posted a message on his Twitter account last night reacting to his country’s win.
It read: “Great job team!”, prompting Celtic supporters to flood his social media page with questions regarding the knock.
He will be assessed by Celtic upon his return to Glasgow over the next 24 hours.
The hopes are back in Scottish Premiership action when they welcome Ross County to Parkhead on Saturday before flying out to Spain ahead of Thursday’s opening Europa League group stage encounter with Real Betis.
Meanwhile, Celtic have received an allocation of 7,400 tickets for their trip to Livingston a week on Sunday.
The West Lothian outfit had to apply for permission from the local Council to increase their maximum attendance due to coronavirus protocols.
The request has been given the green light, with the visitors now expected to fill three-quarters of the stadium.
A club statement read: “Livingston FC is pleased to confirm that West Lothian Council have approved our application for full capacity ahead of our next home game with Celtic on Sunday 19th September here at the Tony Macaroni Arena.
“The club would like to thank West Lothian Council for their assistance and support in getting this approved.”