Franklin Tello made his position clear at the IDV Sports Summit in Ecuador, speaking to DobleCinco.
"The player unfortunately had this injury, but a transaction was reached beforehand, so I believe he is already in a rehabilitation and recovery process."
He went further, predicting a timeline for Mercado's arrival.
"I think the team that bought him will have to welcome him after the World Cup."
And on whether the deal could still collapse.
"I believe this will move forward. Sevilla already bought him, yes."
Sevilla announced in February that an agreement had been reached with Independiente del Valle for the transfer of Mercado, with the physical transfer of the player to be completed during the summer ahead of the 2026-27 season.
The deal appeared solid until March 22, when Mercado ruptured the anterior cruciate ligament and damaged the medial meniscus of his right knee during a league match against Técnico Universitario. His rehabilitation will keep him out for six to eight months.
Former Sevilla sporting director Antonio Cordón indicated before his departure from the club that medical examinations would determine whether the deal proceeded.
Ignacio Navarro, who leads Sevilla's sporting department following Cordón's exit, has not yet issued a public statement confirming or denying the transfer — and it is he who will ultimately make the decision given that the attempted takeover by Sergio Ramos's consortium did not succeed.