Boxing promoter Eddie Hearn says Andy Ruiz Jr has signed to fight Anthony Joshua in Saudi Arabia despite speculation he has not committed to the bout.
The unified world heavyweight champion, has not shared any fight details on social media since the 7 December rematch was announced.
His trainer Manny Robles says "there's a reason why" Ruiz has kept silent.
Hearn, who promotes Joshua, says both fighters signed for this fight. The governing bodies have been informed.