West Ham United have reportedly struck a deal to sign the young Spaniard.
The 18-year-old will reportedly move to the Hammers for a fee between £1.9million and £2.3million while Valencia are also said to have insisted on a buy-back clause.
Martinez is a centre forward who is yet to make his debut for Valencia’s first-team, featuring nine times for their second string to date.
West Ham have impressed with their transfer business since Slaven Bilic took charge and their fans will be hoping the manager has signed another hidden gem following the superb addition of Martin Samuelsen last year.
According to the report, Valencia Mestalla have recently added two new strikers to their ranks, leaving Martinez’s chances limited and prompting the La Liga club to accept West Ham’s offer.
That said, the presence of a buy-back clause shows how highly the teenager is rated and it will be interesting to see how he develops at the Hammers in the years ahead.