User blog comment:Panz Fry/The last Shichibukai/@comment-4899461-20130227135300

If the Z information is to be believed, the pirate that cut off Z's arm 45 years ago later became a Shichibukai, which would make him quite old. This means that each one of the 3 new Shichibukai is from a different generation of pirates: Law from the youngest (and "worst") generation, Buggy from the generation after Roger's, and the new guy from the old generation of Roger and Whitebeard.