A National Basketball Association game between the Brooklyn Nets and the New York Knicks has been called a “Clash of the Boroughs.” “Clash of the Boroughs on 11/26. Check out the tee that we’re giving away @BarclaysCenter #HelloBrooklyn: http://instagr.am/p/SRLISGhFAt/” was posted on Twitter by the Brooklyn Nets on November 20, 2012. People who attended the November 26, 2012 basketball game at Barclays Center in Brooklyn against the New York Knicks got a “Clash of the Boroughs” T-shirt.
 
The “Clash of the Boroughs” term has been rarely used after 2016, with “Battle of the Boroughs” gaining popular acceptance instead.
   
   
Wikipedia: Knicks-Nets rivalry
The Knicks–Nets rivalry is a crosstown rivalry between New York City’s two National Basketball Association (NBA) teams, the New York Knicks and Brooklyn Nets. Both teams compete in Atlantic Division of the Eastern Conference. The New York Knicks were established in 1946 as one of the charter franchises of the NBA, and have been based at Madison Square Garden in Midtown Manhattan since 1968. The Nets were established in 1967 as a member of the now-defunct American Basketball Association, and joined the NBA in 1976. They have been based at Barclays Center in Brooklyn since 2012, though have played in the New York metropolitan area their entire existence.
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After the Nets’ move to Brooklyn, due to the close proximity of the two teams and the overall histories of Brooklyn and Manhattan, media outlets have dubbed the rivalry the Battle of the Boroughs, or Clash of the Boroughs. The two teams have met in the playoffs three times over the course of their history, with the most recent meeting in 2004. This rivalry can also be called the “Cross-Bridges Rivalry”.
         
Twitter
Brooklyn Nets
@BrooklynNets
Clash of the Boroughs on 11/26. Check out the tee that we’re giving away @BarclaysCenter #HelloBrooklyn: http://instagr.am/p/SRLISGhFAt/
5:37 PM - 20 Nov 2012
     
Twitter
Darren Rovell
@darrenrovell
The @BrooklynNets are giving away this “Clash Of The Boroughs” shirt for Nov. 26 game vs Knicks
6:01 PM - 20 Nov 2012
       
25 November 2012, Daily News (New York, NY), “Carmelo’s Hitting All the Right Notes” by Bernie Augustine, Justin Tasch and Michael O’Keeffe, pg. 85:
YOU GOTTA BE SHIRTIN’ ME!
The highly anticipated season opener between the Nets and Knicks was rightfully postponed from its originally scheduled date Nov. 1 in the wake of Hurricane Sandy. But the rescheduled date and the beginning of New York’s new basketball rivalry are finally upon us. Act I will be Monday night when the Nets host the Knicks at the Barclays Center in Brooklyn, and The Score has some good news for fans who have had to wait to attend this crosstown clash: You’re still getting some free swag. The Nets will be giving away T-shirts inside the Barclays Center to commemorate their first New York City showdown with the “Manhattan Knicks,” as Brooklyn borough president Marty Markowitz calls them.
 
The navy blue shirts feature a white outline of a basketball with “Clash of the Boroughs” written inside. Below the ball it reads “Nets versus Knicks,” with the original Nov. 1 date crossed out underneath it by an X, which sits above the new Nov. 26 date. As far as free T-shirt giveaways go, this one seems above average. The crossed-out date isn’t the most clever idea, but it’s nitpicking. And hey, we’re not going to complain about free apparel.
 
Twitter
Josh Newman
@Joshua_Newman
They gave media members ‘Clash of the Boroughs’ tees in the work room. Does that mean I have to be positive when I write later. #journalism
4:03 PM - 26 Nov 2012
   
The Brooklyn Game
In the battle for everything, Brooklyn reigns supreme
by Devin Kharpertian November 27, 2012
11:41 PM - Nov 26, 2012
BROOKLYN, N.Y. — In the Battle for New York AKA the Battle of the Boroughs AKA the Clash of the Boroughs AKA The Thirteenth Game Of The Season AKA The Championship To Win Everything Ever In The History Of Ever, the Brooklyn Nets took down the New York/Manhattan Knicks in overtime at The Black House, 96-89.
 
Grantland
We Went There: The Battle for New York 
NOVEMBER 27, 2012
by BEN DETRICK
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Even in a showdown billed as the “Battle for New York” or the “Clash of the Boroughs” or “A Bunch of Professional Athletes Who Live in Westchester Playing for Franchises Across the Bridge From Each Other,” most Nets fans aren’t emotionally invested enough to curse at every miss.
     
Nets Daily
Clash of the Boroughs, IV: Brooklyn Nets vs. New York Knicks
By Net Income Jan 20, 2013, 4:00pm EST
Normally, the final game of the Nets - Knicks series takes place the last week of the season. Some years, it meant something. Most, it didn’t. The two teams so rarely played well in the same season. This year, the last game take place at the season’s mid-point, Game 41. That means bragging rights have a longer lifespan, at least into the playoffs.
 
Twitter
ParkWhiz
@ParkWhiz
It’s a clash of the boroughs! @BrooklynNets take on the @nyknicks at @TheGarden tomorrow. http://ow.ly/108x1Z
5:45 PM - 31 Mar 2016
 
Twitter
ATC-5
@vvatc5
Tag op insta van @bassiebasic ! ATC-5 present in NYC!! Knicks - Nets, clash of the Boroughs ! Keihard!!
11:31 AM - 21 Oct 2016