“How about that!” (Yankee announcer Mel Allen catchphrase)

“How about that!” was the catchphrase of Mel Allen (1913-1996), the sports announcer who was called the “Voice of the Yankees.” Allen’s 1996 New York (NY) Times obituary states:
 
It was in 1949, when DiMaggio hit four home runs in three games after a long absence because of a heel injury, that Mr. Allen shouted, “How about that!” each time DiMaggio homered. The phrase immediately caught on with fans.
 
This refers to New York Yankee Joe DiMaggio’s performance at Boston’s Fenway Park, June 28-30, 1949. However, “How about that!” is cited in print from September 9, 1949. By October 1949, “How about that!” was being printed on buttons.
   
   
Wikipedia: Mel Allen
Mel Allen (Hebrew name: Mordechai ben Yehuda Elya; February 14, 1913 – June 16, 1996) was an American sportscaster, best known for his long tenure as the primary play-by-play announcer for the New York Yankees. During the peak of his career in the 1940s, 1950s and 1960s, Allen was arguably the most prominent member of his profession, his voice familiar to millions. Years after his death, he is still promoted as having been the “Voice of the New York Yankees.” In his later years, he gained a second professional life as the first host of This Week in Baseball.
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Among Allen’s many catchphrases were “Hello there, everybody!” to start a game, “How a-bout that?!” or “Going, going, gone!” on home runs and “Three and two. What’ll he do?”
   
Google News Archive
9 September 1949, Prescott (AZ) Evening Courier, “Sports Roundup” by Hugh Fullerton, Jr., sec. 2, pg. 3, col. 1:
HOW’S THAT AGAIN?
Direct quote from Mel Allen’s broadcast of the Yankees-Red Sox game Wednesday night: “Well, how about that? Rizzuto made one of the greatest one-handed scoops while going head over heels and tagged Zarilla that you ever saw.”
 
2 October 1949, New York (NY) Times, “Sports of the Times” by Arthur Daley, pg. S2:
They came from behind to take yesterday’s game like true champions. If you’ll pardon the coining of a phrase which Mel Allen eventually will get around to using some day—how about that!
 
12 October 1949, Augusta (GA) Chronicle, Walter Winchell column, pg. 5, col. 2:
Mel Allen’s phrase,“How ABOUT that?” is a big seller (on big buttons) at the ball parks.
 
Google News Archive
27 August 1950, Tuscaloosa (AL) News, pg. 11, col. 4:
Yanks To Honor
Mel Allen today

NEW YORK (AP)—It will be “Mel Allen Day” when the New York Yankees and Chicago White Sox play at the Yankee Stadium this afternoon.
 
Allen, the “Voice of the Yankees” and known by radio fans for his familiar “how about that?” when he describes an unusual play in a game, will be honored with ceremonies which will begin an hour before the game.
 
New York (NY) Times
Mel Allen Is Dead at 83; Golden Voice of Yankees
By RICHARD SANDOMIR
Published: June 17, 1996
Mel Allen, the exuberant Alabaman who turned “How about that!” and “Ballantine Blast” into common parlance during a glorious reign as the voice of the Yankees, died yesterday at his Greenwich, Conn., home some time after watching the Yankees’ game with the Cleveland Indians, his sister, Esther Kaufman, said. He was 83 years old.
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It was in 1949, when DiMaggio hit four home runs in three games after a long absence because of a heel injury, that Mr. Allen shouted, “How about that!” each time DiMaggio homered. The phrase immediately caught on with fans.
 
Google Books
Sports on New York Radio:
A play-by-play history

By David J. Halberstam
Lincolnwood, IL: Masters Press
1999
Pg. 353 (Ten Most Popular Phrases):
Mel Allen…..........“How about that!” anything astonishing
 
OCLC WorldCat record
How about that! : the life of Mel Allen
Author: Stephen Borelli
Publisher: Champaign, IL : Sports Pub., L.C.C., ©2005.
Edition/Format:  Book : English
Summary: “How about that! the life of Mel Allen is the first biography on perhaps the most famous sports broadcaster ...”—Jacket.