Joe Calzaghe says he is considering moving up to fight in the light-heavyweight division.
Calzaghe may add seven pounds to his fighting weight
The unbeaten Welshman said: "The older you get, the bigger you get and the harder it is to make the super-middleweight division.
"I think I've achieved everything I'm going to achieve at this weight."
The 30-year-old has held the WBO super-middleweight belt since October 1997 when he beat Chris Eubank with an emphatic points decision.
Calzaghe admitted he is disappointed not to have secured a lucrative showdown with the likes of American middleweight star Bernard Hopkins.
"I've been champion for six years, I've beaten all the top contenders, so unless other contenders like Hopkins come through then what's the point," he said.
"I'll move up and set myself different goals, different faces and a new challenge, which would be to become a two-weight world champion."
Before that, Calzaghe will defend his WBO super-middleweight title for the 14th time against mandatory challenger Mger Mkrtchyan at the Wales National Ice Rink in Cardiff on 6 December.
And Calzaghe is aiming to put on a good performance for his loyal followers.
"This is a big title defence for me against a tough challenger and I will be counting on my fans to turn up on fight night as they always do to give me great support," he said.