“One’s scared and the other is glad of it” is said of a schoolyard fight or of a boxing match, where one side doesn’t want to fight and the other side is relieved. The saying is recorded by at least 1898 from Texas (and a 2010 citation below claims that it’s “an old west Texas adage”), but the origin of the saying is unknown.
   
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History of the Fifth regiment Maine volunteers, comprising brief descriptions of its marches, engagements, and general services from the date of its muster in, June 24, 1861, to the time of its muster out, July 27, 1864.
By George W. Bicknell
Portland, ME: H.L. Davis
1871
Pg. 261:
It used to remind us of two boys, who wanted to fight most terribly, but whose real status was, “one was scared, and the other durstn’t.”
   
23 October 1898, Dallas (TX) Morning News, pg. 14:
THADDEUS SHERRILL, Mexia, Tex.—
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I guess one was scared and the other glad of it.
 
19 August 1900, Dallas (TX) Morning News, ‘Texas Democrats Separating Into Hostile Camps for a Bitter Factional War,” pg. 3:
To be candid, and gie credit to those who are entitled to it, it is a fact that the applause was so evenly distributed on both sides as to be marked and a topic of conversation, and it seemed to so frighten both factions that “one was scared and the other was glad of it.”
   
14 November 1919, Elkhart (IN) Truth, ‘Two Indiana Football Coaches Decide on College Games in Three-Minute Conversation” by Heze Clark, pg. 6:
In past years in some colleges it has been “one was scared and the other was glad of it.”
   
14 October 1958, Dallas (TX) Morning News, “The Sports Scene” by Bill Rives, sec. 2, pg. 1:
It was strictly a waltz; it looked like one of the fighters was scared and the other was glad of it.
 
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17 October 1958, Spartanburg (SC) Herald, “Peace—In Morality Or Selfishness?” by Roscoe Drummond, pg. 4, cols. 4-5:
So far, since World War II, selfishness has not led to war purely because of the old school yard formula of “Both of ‘em are scared, and the other one is glad of it.”
   
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A Multitude of Men: a novel
By David Anthony
New York,NY: Simon and Schuster
1959
Pg. 201:
“It wasn’t a real fight, even,” Dudley protested. “One of us scared and the other glad of it, was all.”
   
19 June 1959, Frederick (MD) News, “Sweetie Pie” comic, pg. 16, col. 1:
“One’s scared, and the other one’s glad of it!”
(Two boys are sticking their tongues at each other, but they have their hands behind their backs. This line is spoken by one girl to another—ed.)
   
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Little World Apart
By Squire Omar Barker
Garden City, NY: Doubleday
1966
Pg. 51:
They reminded me of a couple of ol’ surlies warily circling each other when one of them is scared and the other glad of it.
 
15 September 1966, Seattle (WA) Daily Times, “We’re Fighting Half-Hearted War” by Carl Rowan, pg. 15. col. 1:
WASHINGTON, Sept. 15.—During my boyhood in Tennessee, we used to gather in the cow pasture behing the Methodist church to play football, always hopeful of seeing a good fistfight when the scrimaging got rough.
 
But occasionally there was great disappointment as two boys, their anger fading rapidly, would dance about without landing a blow worthy of our attention.
 
“One of ‘em’s scared and the other one’s glad of it,” someone would say sarcastically and we would go back to our game.
   
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14 November 1974, Rome (GA) News-Tribune, ‘Vince, Shug sing a song of praises,” pg. 7A, col. 4:
AUBURN, Ala. (AP)—Two teams with a chance to tie Alabama for the Southeastern Conference football championship clash here Saturday when Auburn defends its national rating against Georgia.
 
If you listen to the coaches, each team is scared and the other is glad of it.
   
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3 January 1982, Pittsburgh (PA) Press, “Like Tough Talk In The Schoolyard” by Carl T. Rowan, pg. B2, col. 5:
We ought to understand, however, that what we have is a dangerous schoolyard sort of confrontation between two proud nations, each capable of virtually destroying this planet.
 
In the old schoolyard days there often was a warning, a dare, some angry words, then the two participants would dance around, never striking a blow, with onlookers shouting: “One of ‘em’s scared, and the other’s glad of it!”
 
Not so in the international arena, where the litany becomes: “Both superpowers are scared, and mankind is glad of it.”
 
1 August 1987, Miami (FL) Herald, “Good grapples with evil in Orange Bowl Bash,” pg. 1D:
In boxing, one is scared and the other one is glad of it, so they’re always backing, backing. Here it’s continuous action all the time,” Rotfort said.
   
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The Crusade for Justice:
Chicano militancy and the government’s war on dissent
By Ernesto B Vigil
Madison, WI: Univ. of Wisconsin Press
1999
Pg. 8:
When neither contender in a fight showed “heart,” Gonzales would quip, “One of ‘em is scared, an’ the other’s grateful.”
(Boxer and coach Rodolfo Gonzales, probably in the 1950s or 1960s—ed.)
   
Bleacher Report
Big East Tournament: What To Look For Today At Madison Square Garden
by Barking Carnival
Written on March 11, 2010
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An old west Texas adage about two fellas acting like they want to fight applies to this game. The saying goes, “One fella was scared and the other is glad of it.”