In 2025-2026, Grombahi played 21 games for Sporting CP U23, in which he recorded five goals and four assists across all competitions. He also made four appearances in the UEFA Youth League and made his debut for Sporting CP's first team in the quarterfinals of the Allianz Cup against Alverca in October 2025. In the UEFA Youth League match this season between Sporting CP U19 and Club NXT U19, he was not part of the selection because he was called up for Sporting CP's first team match at that time.
Grombahi comes over on a rental basis until the end of this season, with an option to extend the partnership for three seasons.