Henry Armstrong or Harry Greb - who had the more impressive peak runs?

Harry Greb, 1917-1919 - From 11/19/1917 to 5/5/1920 Greb beat: HOF MW contenders Mike Gibbons and Jeff Smith, MW Champions George Chip and Al McCoy, HOF LHW champs Jack Dillon & Battling Levinsky(four times), and HOF HW contender Billy Miske(twice). He also beat HW contender Bill Brennan(four times), MW contenders Eddie McGoorty, Leo Houck(twice) & Joe Chip (the latter a former conqueror), future LHW champ Mike McTigue(twice), former top HW contender Gunboat Smith, and notable HW journeymen like Willie Meehan & Bartley Madden. Not to mention numerous top middleweight and light-heavyweight contenders sandwiched in between.

His record during that time was 78-0-2.

Greb by a mile, imo.

 

Greb had a 54-0-2 record from 6/2/20 to 2/23/23 (which was broken thanks to the robbery/gift decision given to Tunney by his NY amigos). During that time he beat:

Gene Tunney (should be twice)
Tommy Loughran (3 times)
Tommy Gibbons (twice)
Jeff Smith (three times)
Kid Norfolk

 

This. But I don't understand why the OP is under the impression '18-19 is Greb's "peak"? Just because it includes his undefeated year of 1919.

No one can match what Greb did after 1919. Let alone, compare to him when you include what he also did before. He is the greatest thing this sport has ever seen.

Greb was 9 years of unbridled terror, as far as I'm concerned.

I assembled this a while back:

From February 12, 1917 (defeats Willie 'KO' Brennan) to February 26, 1926 (controversial loss to Tiger Flowers) Harry Greb went 210-7

He defeated such Hall of Famers as:
Kid Norfolk
Mickey Walker
Gene Tunney
Tommy Gibbons 2x
Mike Gibbons
Tommy Loughran 4x
Jack Dillon 2x
Maxie Rosenbloom
Battling Levinsky 6x
Jimmy Slattery
Billy Miske 2x

Defeated such champions (at one time or another) as:
George Chip 2x
Al McCoy 2x
Johnny Wilson 3x
Mike McTigue 2x

Notable Heavyweights defeated:
Bill Brennan 4x
Jack Renault
Charley Weinart
Gunboat Smith 2x
Homer Smith
Martin Burke
Willie Meehan 2x
Bob Roper 6x

Other notable victories:
Clay Turner
Tommy Robson
Silent Martin
Joe Borrell
Leo Houck 3x
Soldier Bartfield 3x
Eddie McGoorty
Gus Christie
Terry Martin
Buck Crouse
Frank Mantell
Willie 'KO' Brennan
Jeff Smith 6x
Jimmy Darcy 2x
Chuck Wiggins 8x
Billy Shade 2x
Lou Bogash
Bryan Downey
Jackie Clark 2x
Frank Moody
Ted Moore 2x
Jimmy Delaney 3x
Augie Ratner 2x
Jack Reddick
Roland Todd

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