“Summer league can’t tell you who can play, only who can’t” (basketball adage)

The NBA holds summer leagues for rookies and free agents who are trying to prove themselves and get a spot on a professional basketball roster. The saying about summer league is that it doesn’t tell you who can play in the NBA, but it definitely tells you who can’t play there. That is, a poor showing disqualifies a player, but a good showing in summer league doesn’t necessarily mean that the player can make it in the NBA.
 
“Maybe more than finding out who can play, the Summer League gives coaches a feel for who can’t play” was cited in coach Eric Musselman’s website on July 10, 2008.
 
   
Eric Musselman’s Basketball Notebook
Thursday, July 10, 2008
How Hubie Brown ran his Summer League team
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Maybe more than finding out who can play, the Summer League gives coaches a feel for who can’t play.
   
TSN
CHISHOLM: BREAKING DOWN THE RAPS’ SUMMER LEAGUE PERFORMANCE
Tim Chisholm
7/17/2009 5:43:08 PM
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Of course, the cardinal rule remains, and that is Summer League doesn’t tell who can play in the NBA, it only tells you who cannot.
     
LakerNation Forums
TheCalmInsanity
Posted July 22, 2009 - 02:07 AM
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I’m a firm believer that summer league means nothing. More than showing you who can play in the NBA, it shows you who CAN’T play in the NBA.
   
National Post (CA)
Five questions heading in Raptors camp
Eric Koreen | 10/09/28 | Last Updated: 10/09/27 5:47 PM ET
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However, you know what they say about summer league: It does not definitively reveal who can play in the NBA, just who cannot.
 
Bleacher Report
NBA Summer League 2013: Veterans With Most to Prove This Offseason
By Tyler Conway (Featured Columnist)  on July 8, 2013
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As Bruce Arthur of The National Post pointed out on Twitter yesterday, there is only one law of NBA Summer League play:
 
Bruce Arthur
@bruce_arthur
It’s awesome that Kelly Olynyk was great today, but again, the rule of NBA Summer League is it can’t tell you who can play; only who can’t.
7:04 PM - 7 Jul 2013
 
NBC Sports
Five players who have stood out at the Orlando Summer League
Kurt Helin
Jul 9, 2013, 2:17 PM EDT
Be careful about reading too much into success at NBA Summer League — the old adage is Summer League doesn’t tell you who can play in the NBA, only who cannot.
 
The Province (British Columbia, Canada)
Gallagher: Kamloops’ Kelly Olynyk lighting up NBA summer league for Celtics
Kamloops product second in league scoring as he impresses the Celtics, media ... and everyone else
By Tony Gallagher July 13, 2013
One of the most often trotted-out clichés about the NBA summer league is that it doesn’t tell you who can play in the League, but it tells you who can’t.
 
And if there is one thing that Kamloops’ Kelly Olynyk proved during his rigorous week in Orlando playing for the Boston Celtics summer league team this past few days, it’s that he certainly didn’t disqualify himself.