The 16-year-old will officially link up with the Premier League side after turning 18, with the agreement allowing him to remain in Ecuador until the summer of 2027 as part of his development pathway.
Despite his age, Martinez had already attracted significant attention across Europe, with Newcastle beating competition from FC Barcelona and Bayer Leverkusen to secure his signature.
The deal reflects a continued emphasis from Newcastle’s hierarchy on long-term recruitment, with sporting director Ross Wilson outlining the club’s strategy in targeting emerging talent from elite development systems.
Wilson highlighted Independiente del Valle’s growing reputation as a production line for top-level players, a factor that played a key role in Newcastle’s decision to invest early in Martinez’s potential.
The Ecuadorian side has become one of South America’s most respected academies in recent years, consistently producing technically gifted players ready to transition into European football.
Martinez will now continue his progression in that environment while Newcastle monitor his development closely, maintaining regular contact ahead of his eventual move to England.
For Newcastle, the agreement mirrors a wider trend among leading European clubs seeking to secure elite prospects earlier, particularly from South America, where competition for emerging stars has intensified.
While Martinez is not expected to impact the first team in the immediate future, the club views him as a player with significant upside, capable of developing into a key asset over time.
The move underlines Newcastle’s dual-track approach: balancing present-day ambitions in the Premier League with calculated investments in the next generation.