Wales Head Coach Warren Gatland has confirmed fly-half Dan Biggar has suffered a "high ankle sprain" in Wales' 16-all draw with Ireland.
Wales' number 10 had to come off mid-way through the first half after he picked up the knock in the game's opening phases.
Gatland said it was too early to tell if the 26-year-old will miss next week's game with Scotland and his injury will be fully assessed tomorrow.
Wales have drawn 16 all against Ireland in their opener of the Six Nations.
In the second half Wales continued their resurgence with Rhys Priestland tying the game with an early penalty.
Just ten minutes to go and Jonny Sexton struck back.
Wales now must prepare against Scotland at the Principality Stadium next week.
At half time Ireland lead Wales 13-10 in a pulsating opening Six Nations clash between the two sides.
Ireland got the first points of the game courtesy of two Jonny Sexton penalties.
The home side also scored the game's first try through scrum-half Conor Murray.
Wales struggled in the opening 20 minutes with Dan Biggar going off early with an ankle injury.
But Taulupe Faletau went over just before the break helping to bring Wales back to within three points of the home side.
Network Rail has advised train passengers across South and West Wales to check before they travel as the regions brace for the arrival of Storm Imogen.
A yellow weather warning is in place from 3am on Monday morning until late afternoon with weather forecasters predicting strong winds and heavy rain.
Cautionary speed restrictions will be in place on lines across South and West Wales.
Network Rail's frontline teams are on alert, ready to tackle any problems the storm may cause to the railway.
The heavy rainfall across South Wales on Saturday saw flooding at a number of locations with temporary line closures and speed restrictions affecting journeys.
Network Rail workers have been out in force clearing drainage systems of debris, but with rain falling on already saturated ground, there is the potential for localised flooding.
South Wales Police is appealing for information concerning the whereabouts of Ian Campbell, 36, who has been reported missing.
Officers want to trace Ian, who is from the Mountain Ash area, as they are concerned for his welfare. He was last seen on Friday 5 February 2016.
Anyone who knows of Ian’s whereabouts is asked to contact South Wales Police on 101 or call Crimestoppers, anonymously, on 0800 555111 and quote reference: 1600041912.
Liam Williams will start at 15 for Wales in this afternoon's Six Nations game with Ireland after a hamstring injury ruled out Gareth Anscombe.
The New Zealand born fullback is expected to train fully next week ahead of Wales' home game with Scotland.