History question about russian royalty?

Question

Tsarevna was the title of the daughter of the tsar of russia but was was the title of the person she marries, whi has no relation to the tsar. what would their title be?

Answer 1

prince/duke or whatever his title currently was- until they take the throne where he would then become czar.

Answer 2

His title would countinue to be whatever his title is and he WOULD have a title as a Russian princess would never be allowed to marry a commoner.  He would not inherit the throne but rather it would go to the next male heir.