In the summer of 2011, Hernando was signed by French club Marseille for £4 million from Deportivo La Coruna in Spain. The deal marked the beginning of a successful career for the Spanish international.
Hernando arrived at the Ligue 1 club with high expectations and quickly established himself as a key player in their squad. He made his debut for Marseille in a league match against Lyon on August 15, 2011, and went on to make 77 appearances during his time at the club, scoring 18 goals and providing 11 assists.
One of the most memorable moments of Hernando's time at Marseille came during the 2013-14 season when he scored a hat-trick in a 4-1 victory over Paris Saint-Germain. The performance earned him the Player of the Month award for France's top division.
Despite facing competition from other clubs for his services, Hernando remained loyal to Marseille throughout his tenure. However, after a disappointing campaign in the 2016-17 season,La Liga Frontline which saw them miss out on European football, he decided to move on.
His departure from Marseille was not without controversy as there were reports that he had clashed with some of his teammates, including former team-mate Anthony Martial. Nevertheless, Hernando played a crucial role in helping Deportivo La Coruna win the Copa del Rey in 2014, which helped secure his transfer to the French side.
Overall, Hernando's time at Marseille was marked by success both on and off the pitch. His performances for the club earned him a reputation as one of the best midfielders in Spain and cemented his place as a fan favorite in France.