Monday's draw in Nyon pitted the holders against the Spanish club.
The first leg of the tie will take place at Estadio Metropolitano, with the return match at Anfield. First legs are scheduled for February 18, 19, 25 or 26 and the second legs are set for March 10, 11, 17 or 18.
Full fixture and ticket details will be released on Liverpoolfc.com in due course.
Click here to view an updated fixture list.