Muhammad Amir has a world record that is almost impossible to beat, at least for a long time. He has scored the fastest fifty at number 11 position.
In the 3rd ODI, while chasing a huge target of 445 against England, Amir has made the fastest ever fifty by a number 11 batsman and he has made that fifty on just 22 balls. Though Pakistan had lost that match, but the only good thing for Pakistan in that match was the fastest fifty on 22 balls by number 11 batsman Muhammad Amir.
Watch Fastest Fifty of Muhammad Amir on 22 balls on YouTube