It's pretty rare that an unseeded player comes along that looks like their A-Game can match the A-Game of the Federer/Nadal/Djokovic class but Chung looks like he has it. Like even guys like Zverev and Dimitrov don't feel like they have a great chance against Fed/Nadal if Fed/Nadal are playing their best, but Chung feels like he has a better chance of hanging with them. Just has that unique ability to turn defense to offense so quickly.