The Noble Qur'an came to Nabi Muhammad Alaihi Salaat-u-Wassalam. One cannot be understood without the other. Having said that, if any Hadith is in conflict with the Noble Qur'an, then it is the Noble Qur'an whom we put first and foremost. It is our job to study the Noble Qur'an and find the harmonious whole between the two.The Holy Qur'an makes no mention of any such Saviour/Messiah/Mehdi ..
However, what the Holy Qur'an does mention is:
"....Surely Allah does not change the condition of a people until they change their own condition; and when Allah intends evil to a people, there is no averting it, and besides Him they have no protector" (ar-Ra'd: 11)