Fun logic puzzle

This is a fun logic puzzle:

"In Transylvania, there were 10 magic sources of potion. These were labeled 1, 2, 3,..., 9, 10. If you drank a poison, you can only be cured by drinking one with a larger number. So if you were to drink 2 then you would need to drink any potion greater than 2 to live.

A very evil wizard controlled potion 10 (note: this is the highest potion.) He would have drinking competitions with others. (A drinking competition being the challenger drinking whatever the wizard gives, and the wizard drinking whatever the challenger gives.) Usually the wizard would just give potion 10 to the other guy (thus the other guy would die) and whatever liquid the challenger gave to him he would take 10 to be cured.

However, one fine day, the challenger survived and the wizard died in this competition. How is it possible?"

The wizard was the challenger, and the other wizard was hosting the competition