Michael Spinks was a beast at Light Heavyweight, he went toe to toe with Yaqui Lopez and won a war. Also his KO over Marvin Johnson was excellent, Michael Spinks has got to be one of the most underrated fighters because he got blew away by Mike Tyson.

Also Qawi, Muhammad, two of the most action packed Light Heavyweight's. Great fighters and they produced some classic fights.

You don't get Light Heavyweight's like those anymore.

As for the topic yes i believe there's quite a few, who could easily challenge Rocky Marciano and win.

Some fighters who would have a good chance at there best, between Light Heavyweight and Cruiserweight.

Dwight Muhammad Qawi
Michael Spinks
Ezzard Charles
Archie Moore
Evander Holyfield
Floyd Patterson
Bob Foster
Roy Jones Jr
Billy Conn
Michael Moorer