I have to give Marciano a chance because of reasonable triangulation-Frazier would likely beat him with relentless pressure, & swarmers have the stylistic advantage over boxers. And it seemed to go that way in sparring... However Marciano is smaller overall than Frazier, & the size gap with Holmes would likely make a difference. With all those jabs he would be eating & his skin he might cut badly. DJ Sanders at I believe 96 may well kick both of our asses-then have Crosstrainer for dessert. Even though the latter seems like a real fighter of sorts.