“Getting good players is easy; getting them to play together is the hard part” has been credited to baseball manager Casey Stengel (1890-1975). Stengel was manager of the New York Yankees from 1949 to 1960; he had many good players and got them to play together to win world championships.
 
Stengel is has been credited for the quotation since at least the 1980s and 1990s, but the exact form and date of the quotation is unknown.
 
 
Wikipedia: Casey Stengel
Charles Dillon “Casey” Stengel (/ˈstɛŋɡəl/; July 30, 1890 – September 29, 1975), nicknamed “The Old Perfessor”, was an American Major League Baseball outfielder and manager. He was elected to the Baseball Hall of Fame in 1966.
 
Stengel was born in Kansas City, Missouri, and originally nicknamed “Dutch”, a common nickname at that time for Americans of German ancestry. After his major league career began, he acquired the nickname “Casey”, which originally came from the initials of his hometown (“K. C.”), which evolved into “Casey”, influenced by the wide popularity of the poem Casey at the Bat. In the 1950s, sportswriters dubbed him with yet another nickname, “The Old Professor” (or “Perfessor”), for his sharp wit and his ability to talk at length on anything baseball-related.
 
Although his baseball career spanned a number of teams and cities, he is primarily associated with clubs in New York City. Between playing and managing, he is the only man to have worn four of New York’s major league clubs’ uniforms. He was the first of four men (through the 2010 season) to manage both the New York Yankees and New York Mets; Yogi Berra, Dallas Green, and Joe Torre are the others.
 
Google Books
International Industrial Engineering Conference Proceedings
Institute of Industrial Engineers (1981- ). Toronto Chapter
1989
Pg. 274:
Casey Stengel said, “it’s easy to get the players for a team…getting them to play together is the hard part.”
 
Google News Archive
6 September 1991, The Ledger, “Letters,” pg. 6A, col. 5:
As Casey Stengel once said, “Gettin good players is easy. Gettin’ them to play together, that’s the hard part.” Early release days, hopefully, will address this problem.
BECKY REEVES
President
Polk Education Association
Bartow
 
Google Books
TeamBuilt:
Making Teamwork Work
By Mark Sanborn
New York, NY: MasterMedia Publishing Corporation
1992
Pg. 114:
Baseball legend Casey Stengel once said, “It’s easy to get good players. Getting them to play together, that’s the hard part.”
     
Google Books
You Can Observe a Lot by Watching:
What I’ve learned about teamwork from the Yankees and life
By Yogi Berra with Dave Kaplan
Hoboken, NJ: John Wiley & Sons, Inc.
2008
Pg. 186:
“Finding good players is easy,” Casey used to say, “getting them to play as a team is another story.”
 
Google Books
An Integrative Approach to Leader Development:
Connecting Adult Development, Identity, and Expertise
By David V. Day, Michelle M. Harrison and Stanley M. Halpin
New York, NY: Psychology Press
2009
Pg. 159:
Finding good players is easy. Getting them to play together as a team is another story. —Casey Stengel
 
Twitter
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‏@99u
“Gettin’ good players is easy. Gettin’ ‘em to play together is the hard part.” - Casey Stengel on Collaboration
9:01 AM - 9 Mar 12
 
Google Books
Managing the Unmanageable:
Rules, Tools, and Insights for Managing Software People and Teams
By Mickey W. Mantle and Ron Lichty
Upper Saddle River, NJ: Pearson Education, Inc.
2013
Pg. ?:
Gettin’ good players is easy. Gettin’ ‘em to play together is the hard part. —CASEY STENGEL