The Spaniard has failed to score in any of his 13 appearances for the Saints, who are reportedly set to offload him to Real Sociedad.
The Spaniard arrived at St Mary's for £5 million from Malaga last summer, signing a four-year deal with Ronald Koeman's side.
But having failed to find the net in 13 appearances, his time on the south coast looks poised to come to an end, with El Diario Vasco suggesting a move to the Anoeta Stadium is increasingly likely.
The 22-year-old has reportedly been in talks with the Liga club for several weeks and has seemingly agreed personal terms.
The Basque newspaper claims the club are now looking to agree a fee with the Saints, with a £1.5 million fee mooted.
However, Southampton are thought to be looking for nearly double that amount as they look to recoup the money paid out for him only last summer.