The defender scored in both the semi-final and final of the Champions League and has been backed to be a leading contender for the game's biggest personal prize
The 28-year-old scored twice in the Champions League semi-final second-leg victory over Bayern Munich and then headed home a dramatic injury-time equaliser against Atletico Madrid in the final.
Lionel Messi and Cristiano Ronaldo have won the award for the last six years, but Sanchis believes the time has come for the Madrid defender to be recognised for his efforts at both ends of the pitch.
Sanchis said: "We've known for a long time that Ramos is the best defender in the world, I've never doubted that.
"I already put him amongst the candidates for the Ballon d'Or. A player of his quality and performance has to be considered.
"I have a theory that teams are built from back to front. The centre of defence is crucial because you have the ability to dictate and Sergio influences because his game is not only defence. He's a complete player."
Ramos joined Madrid from Sevilla in 2005 and has gone on to make nearly 300 appearances for the club.
He has also enjoyed incredible success with Spain, having won the World Cup once and European Championship twice.