Depends on the calibre of the fast med seam bowler, dont it. Is he only club standard, shield class or is he Clarke or Siddle class. Two guys that should know the ability of a cricketer, Ricky Ponting and Brian Lara rate Josh Hazlewood. Lara said he is as dangerous a bowler as the great Glenn McGrath while Ponting said his relentless chipping away in that 6-8 metre zone makes him a very difficult bowler to face because of the pressure he builds..
Hazelwood is a world class bowler and we are not likely to replace him with a bowler of similar quality. But his role in the team is the easiest one to replace, we lack many types n the domestic scene but we have heaps of right arm seamers who bowl 135kph. The bloke who is with the squad does that.