He looks set to be joined on the sidelines by lock forwards Scott Cummings and Jonny Gray who were also injured in the defeat.
Russell looked groggy as he went off after 63 minutes and is unlikely to be able pass the return-to-play protocols with such a quick turnaround.
It leaves head coach Gregor Townsend with big problems at stand-off as Scotland look to get their campaign back on track after consecutive home defeats against Wales and Ireland.
Adam Hastings, Scotland’s second choice No 10, is suspended for the Italy game following his red card for Glasgow against Leinster last month.
Jaco van der Walt, the Edinburgh fly-half, failed to make the bench for the Ireland game and has yet to see a minute of action in the Six Nations after being an unused substitute against England and Wales.
Duncan Weir, who won a Scotland recall during the Autumn Nations Cup, is recovering from a serious shoulder injury and may not play again this season.
Townsend preferred to use Stuart Hogg as his back-up 10 against Ireland, switching the Scotland captain from full-back after Russell went off.
“Finn went off with a concussion so it’s unlikely he will feature in six days’ time,” said the Scotland coach. “We fear Scott Cummings has a hand fracture – and that would keep him out next week. Jonny Gray had a shoulder issue so we’ll wait and see. I imagine more players will come to training on Tuesday sore.”
Townsend wouldn’t rule out the possibility of utilising Hogg at stand-off again against Italy or asking Harlequins centre James Lang to play there. Two young No 10s, Ross Thompson and Nathan Chamberlain, played well for Glasgow and Edinburgh respectively over the weekend but a move to Test level would represent a big jump.
“We have to see,” added Townsend when asked about Thompson and Chamberlain. “We have Jaco van der Walt in the squad and Stuart Hogg played well at 10. James Lang has played 10 at his club a few times. Adam Hastings will be back for the week after [when Scotland are due to play France] so there are players we would look to first.”
The bonus-point defeat by Ireland leaves Scotland fifth in the Six Nations table on six points. They outscored the Irish by three tries to two, with Russell producing a smart improvised score in the first half and Huw Jones and Hamish Watson touching down in the second period as the home side clawed back a 24-10 deficit to draw level before Johnny Sexton’s late penalty won the game for Ireland.
Ireland scored early tries in each half through Robbie Henshaw and Tadhg Beirne but there was a question mark over whether the latter score had been properly grounded. Romain Poite, the French referee, awarded the try without recourse to the TMO.
“The one replay I saw I didn’t think he grounded it,” said Townsend. “But whether that was the case in other replays I don’t know. Poite thought he saw it grounded. It was similar to Hamish Watson’s, which did go to the TMO.”