Hard to tell as his career suffered at times due to injuries that sidelined rather than him gaining momentum.
I prefer his performance over Lacy to Kessler as he was punching with authority in the fight while against Kessler he didn't have the power and only through really solid shots when going for the body.
The Kessler fight while a great win signalled the decline of Joe - he was slightly passed his best that night and his hands were gone.
Possibly 2000 onwards was his prime from the Sheika fight to the Lacy fight but still at times he was sidetracked by hand injuries - also an ankle injury.
Great fighter and I agree with many like Master, Fenster, Tins and Ross regarding the physical and mental (experience) primes. Lennox Lewis is another who it is hard to pinpoint a prime.
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