A “splash play” in football is a play that makes a big splash—that is, it makes a big impact on the game. A “splash play” might be a quarterback sack, a tackle for a loss, a fumble recovery, or an interception. “Splash play” has been used to describe a big play made by a defense, although it could potentially also be used to describe a big offensive play.
 
“Splash play” has been cited in print since at least 2004.
 
   
29 August 2004, Sarasota (FL) Herald-Tribune, “Nece grab”:
There must something about the Miami Dolphins that brings out the best in Ryan Nece. Tampa Bay’s third-year linebacker, who is fighting to keep his roster spot, made the kind of splash play that a player in his position needs to make, in the last game before the first round of NFL roster cuts.
   
Tampa Bay Times (FL)
For Gruden, a new type of screen play
By RICK STROUD
Published May 20, 2005
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MAKING A SPLASH: Rookie receiver Larry Brackins, the fifth-round pick from Pearl River Community College, is proving he can compete. The 6-foot-4, 203-pounder has made some dazzling catches during full-squad, voluntary workouts this week. “I’ll tell you what, the big fella got up today and made a hell of a catch,” Gruden said. “He’s a freak. Down the field (Wednesday), he made a big splash play. ... If we can train this wild horse, that’s kind of what I refer to him as, who knows? You might have a stallion there.”
     
ESPN
New sod creates problems during rain-soaked MNF game
Associated Press
Updated: November 28, 2007, 12:42 AM ET
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Steelers coach Mike Tomlin often talks about splash plays—big plays that make a major difference in a game—but every play on this rainy night in Pittsburgh was a splash play.
 
Pittsburgh (PA) Post-Gazette
Steelers’ fourth-quarter drive sets up winning FG by Jeff Reed
November 17, 2008 12:00 am
By Ed Bouchette
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“James Harrison continues to make splash play after splash play for us,” Tomlin said of his Pro Bowl linebacker who recorded his 12th sack of the season on the safety.
   
Bucs Blitz
Buccaneers reinstate Arron Sears
By The Sports Xchange
Posted Nov 18, 2009
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“We have to go out there and get better with technique. We have to go out there and see somebody make a splash play.”
(Coach Raheem Morris on the Tampa Bay defense—ed.)
 
Blogging the Boys (Dallas Cowboys)
Cowboys O-Line: Successful Against The Splash Play?  
By One.Cool.Customer on Feb 1, 2011, 11:30a
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The basic idea behind pass protection is to keep the opposing defenses from making what NFL scouts call splash plays - plays that turn games around. Splash plays include sacks, QB hits, QB pressures and penalties. The fewer of these an offensive lineman allows, the better.
 
Blogging the Boys (Dallas Cowboys)
Cowboys O-line: Defending The Splash Play
By One.Cool.Customer on Oct 26, 2011, 6:30a
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That is the reality offensive linemen have to live with. For the most part, they get noticed only when they make mistakes or allow what NFL scouts call splash plays - plays that turn games around. Splash plays include sacks, QB hits, QB pressures and penalties.

The fewer of these an offensive lineman allows, the better.
 
Bob’s Blog
Friday, July 20, 2012
Splash Plays 2011 - Part 1
“He’s really starting to make a lot of splash plays. We don’t like those on offense. But, a splash play is when you have a big hit. Big hit on a running back. Big hit on a wide receiver. Big hit on a quarterback. Or just making a tackle for a loss. Just making that impact play is what they call a splash play. He makes a lot of those.” - Davin Joseph on Navarro Bowman
 
The above quote was from the NFL Network’s summer time-killing series, NFL’s Top 100.
 
Blogging the Boys (Dallas Cowboys)
How Successful Was The Cowboys Offensive Line Against The Splash Play?
By One.Cool.Customer on Feb 1, 2013, 8:59a
The fewer splash plays an offensive lineman allows, the better. Today we’ll look at how many splash plays the Cowboys’ linemen gave up and compare that against the NFL average in 2012.