Barcelona star Sergio Busquets is set to miss the second leg of the Copa del Rey quarter finals against Real Sociedad on Thursday night (26 January) after scans confirmed he suffered "a sprained external lateral ligament in his right ankle" during the 4-0 victory over Eibar. The club have failed to set a timeframe in his recovery but reports in Spain suggest that he could be on the sidelines between 10 and 15 days.

The 28-year-old midfielder was forced off in the eight minute of the game at Ipurua following a heavy tackle in his ankle from Gonzalo Escalante. The Spain international was consequently stretchered off and replaced by Denis Suarez amid suggestions he could have damaged the ligaments of his ankle.

Barcelona later played down those fears on Twitter after claiming that initial scans suggested that the Spaniard only had a sprained external lateral ligament in his right ankle.

Busquets has undergone further tests on Monday morning to know the exact extensions of the injury and the results confirm the minor blow.

"After the injury picked up on Sunday in Ipurua in the 4-0 victory over Eibar, Sergio Busquets has undergone tests to find out the exact extent of the problem. The midfielder left the field on a stretcher in the 8th minute of the first half after a challenge from Gonzalo Escalante. Results on Monday confirm that Busquets has a sprained external lateral ligament in his right ankle. The player is out and his return will depend on his recovery," Barcelona confirmed. "This season Sergio Busquets has played 27 of Barça's 32 games, showing just what an important part of Luis Enrique's squad he is."

Barcelona have failed to set a deadline in his return to action but he is definitely out for the Copa del Rey visit of Real Sociedad, with the Catalans having a 1-0 advantage from the reverse fixture played at San Sebastian.

Yet, reports in Spain suggest that the key Spanish midfielder is also a major doubt for the coming La Liga encounter with Real Betis (29 January) and Athletic Club Bilbao (4 February) as he could be out of action for up to 15 days.

The news is the third blow for Luis Enrique in the last seven days after last week the boss also lost Rafinha Alcantara and Andres Iniesta due to different muscle injuries.

Rafinha Alcantara has missed the last two wins over Real Sociedad and Eibar and is still a doubt whether he will be ready to return to action for the Copa del Rey decider. Meanwhile, captain Iniesta could also miss the clash with Real Sociedad after suffering an injury in his soleus during the reverse fixture played at Anoeta.

Barcelona are yet to give any update on both midfielders but neither of them appear in the video released by the club during the Monday's training session.