First winger George North was carried off the pitch on a stretcher during the Pro12 clash between the Scarlets and Ulster.
His injury gives Wales a worry ahead of their Six Nations fixture against Ireland next month.
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Wales scrum-half Gareth Davies says the Scarlets mean business in Saturday's European Champions Cup semi-final against Leinster.
The MP has become Welsh Labour's first deputy leader after the result was announced at the Welsh Labour conference in Llandudno.
At Welsh Labour's conference Carwyn Jones is expected to make a speech containing pledges for his party and the wider public