Liverpool’s search for a new holding midfield player is stepping up. On Tuesday, it was reported by The Athletic that a mystery number six was being targeted by Liverpool, and a number of links have emerged over the past 24 hours. Alan Varela was initially linked as this mystery player, but now, another name has emerged. Indeed, according to Fabrizio Romano, Liverpool are now exploring a move to sign Martin Zubimendi from Real Sociedad with talks set to start shortly. READ MORE: Brazilian player now admits he would love to join LiverpoolLiverpool exploring Martin Zubimendi moveAccording to Rom…