Any classic examples of this? From the UK we recently had Gal Yafai vs Gavin McDonnell and Zelfa Barret vs Ronnie Clark.
Mauricio Herrera did it twice in one year against Jose Benavidez and Danny Garcia but got robbed both times.
Katsunari Takayama vs Riku Kano Daisuke Naito Vs Daiki Kameda Maybe not so much shot down but... Still the youngsters were both given a lesson
Prescott was 25 at the time, Khan was younger than Precott by quite a lot, but Prescott wasn't old at the time and he was 17-0 something like that
Ali-Foreman Schmeling-Louis I Duran-Barkley Langford-Wills V Ortiz-Laguna III Pacquiao-Thurman Gavilan-Ortega I Saddler-Elorde II Gonzalez-Yafai Harada-Famechon I Morales-Pacquiao I Not all fit the bill of 'shot down', if that's supposed to mean KOs but all were pretty spectacular past prime performances or wins.
Pacquiao had almost 40 fights by this time, hardly a novice. I would also say Thurman was slightly past young gun by this point.