Gyokeres left Sporting for Arsenal last month after two seasons of outstanding goalscoring. Similarly, Al-Nassr star Ronaldo left Sporting for England and Manchester United at the beginning of his career.
Reflecting on Sporting's title chances this new season, Ronaldo told Goal: "I hope it's a competitive league. I always hope for the best and that Sporting can be champions again.
"Gyokeres? We only miss those who are there, that's what they say. I believe Sporting will be competitive.
"Gyokeres was a special player, but the team will have to adapt. I believe (Luis) Suarez, who arrived from Almeria, is an excellent forward. (Conrad) Harder is also a good player, young, and needs time. I saw the Super Cup; Sporting performed well against Benfica, but they didn't win because they couldn't—that's football."