Liverpool midfielder Lucas Leiva is expected to be sidelined for up to two months by a knee ligament injury.
It is understood the Brazil midfielder has damaged the medical collateral ligament in his right knee.
Although not as serious as injury to a cruciate ligament – the 27-year-old ruptured the anterior cruciate ligament in his left knee in November 2011 – it will still keep the midfielder out for six to eight weeks.
Lucas sustained the injury just 20 minutes after coming on at half-time in Saturday's 2-2 draw at home to Aston Villa.
He told manager Brendan Rodgers he heard 'a click' in his right knee following a challenge with Fabian Delph.