ATG Fighters Who Lost There Biggest Fight?

[Southpaw Great]

Name some ATG fighters who lost there biggest fight of there career?

Hagler against Leonard?
Jeffries against Johnson?

[Sugarj]

Michael Spinks vs Mike Tyson

Ali in his first fight with Frazier (this is debatable as to if it was Ali's biggest fight)

[DeepSleep]

Liston vs. Clay
Oscar vs. Floyd

[NChristo]

Patterson - Liston
Foreman - Ali
Ketchel - Johnson
Hearns - Hagler (Arguably Hearns' biggest fight.)

[BigStereotype]

Liston vs. Clay
Oscar vs. Floyd

No, more like Oscar vs. Tito, but still him.

Foreman - Ali
Cotto - Margarito (Whether or not he's an ATG is debatable, but he was definitely on that path)
Tyson - Holyfield
Liston - Ali
Ali - Frazier (FOTC was maybe his biggest fight, toss-up between that and Foreman)

[Bundana]

Carpentier vs Dempsey
Moore vs Marciano
Arguello vs Pryor

[boxing boy]

Michael Spinks vs Mike Tyson

Ali in his first fight with Frazier (this is debatable as to if it was Ali's biggest fight)

The 1st Ali-Frazier fight was The fight of the century!! So I believe it was the biggest fight ever,and Ali's biggest fight.

[Sugarj]

Well it was 'billed' as fight of the century and the fight was terrific but it wasn't necessarily the 'biggest fight ever'.

There have been much bigger comparative purses, bigger fight attendances, bigger broadcast exposures, more live viewers, more punches landed. Some might say that Ali Frazier 3 was more entertaining. Ali vs Foreman and Ali vs Spinks 2 were big events featuring Ali too.

Tyson vs Spinks was enormous for example post 1971. Tyson vs Lewis was huge too.

[r.burgundy]

foreman/ali
tito/hopkins
oscar/tito
hearns/hagler
toney/roy jones
qawi/holyfield
kostya/hatton
whitaker/chavez was a draw
vitali/lewis
barrera/pacman

[Sugarj]

Hamed vs Barrera

I'd argue that the first Pacquiou fight for Barrera wasn't anywhere near as big as the Hamed fight. Pac wasn't expected to win and wasn't anything like as big a draw back then.