Dan Biggar is set to miss the rest of the Six Nations and may struggle to return this season after suffering a knee injury playing for Northampton.
The injury was initially described as “not serious” by Saints coach Chris Boyd, but club sources have since admitted that Biggar has sustained significant damage and will be sidelined for “several weeks”.
That would put the 30-year-old out of next week’s game against England at Twickenham and the final round of the Six Nations at home to Scotland on March 14.
It would leave Wales with Cardiff Blues’ Jarrod Evans as the only fit fly-half in the squad for their penultimate tournament game against Eddie Jones’s resurgent England on March 7.
Wales have already lost Owen Williams for the remainder of the tournament with a hamstring injury, while Gareth Anscombe is a long-term injury absentee with a knee problem suffered before the World Cup.
Biggar had to be helped from the pitch at Franklin’s Gardens after 20 minutes of the Gallagher Premiership match against Saracens.
The former Ospreys No.10 kicked a high ball, winning the aerial battle with Saracens centre Duncan Taylor. However the fly-half landed awkwardly on the turf, falling to a seated position. His difficulty was not helped by a Saracens player falling over him as he placed the ball backwards at the resultant breakdown.
Play was stopped in the subsequent phase for medical teams tending to both Taylor and the Wales international. Taylor played on, but Biggar hobbled off with the assistance of medical staff, appearing in some discomfort with his right knee.
Evans is the only other fly-half in the Wales squad presently, meaning a call up for the Dragons’ Sam Davies could be in the offing.
Rhys Priestland called also be called up despite playing in the Premiership and being under the 60-cap threshold for Wales players based outside the country – but only if the Welsh regions agree to it.
Wing George North also remains a doubt to face England as he undergoes head injury protocols after being forced off against France.