Liverpool boss Brendan Rodgers has reportedly made Real Sociedad defender Inigo Martinez one of his leading targets this summer.
Martinez, who has spent his entire professional career at Sociedad, is widely regarded as one of the best young centre-backs in European football.
Barcelona and Real Madrid have both been linked with the Spaniard in recent seasons, but according to El Confidential, Liverpool scouted the 23-year-old during Sociedad's 2-0 defeat at Barcelona on Saturday.
Sociedad are desperate to keep the centre-back, but with Liverpool said to be preparing an offer in the region of £25m, a decision will need to be made this summer.
Martinez made his senior debut for Spain in August 2013.