Guendouzi is currently out on loan at Hertha Berlin until the end of the season, while Ozil continues to be frozen out while his contract runs down.
In a social media Q&A, Ozil was asked the most underrated player he had played with and Ozil replied: "@MatteoGuendouzi - I'm sure he will be a big football player one day!"
And Guendouzi was more than delighted with Ozil's compliment.
Responding to his tweet, 22-year-old Guendouzi wrote: "Thank you my bro @MesutOzil1088. You know how much these words are important for me especially from you, one of the best player[s] in the world and the best I played with."