J.R. Smith ejected after flagrant foul on Jae Crowder in wild Cavs-Celtics Game 4

Cleveland Cavaliers guard J.R. Smith was ejected from Sunday's Game 4 against the Boston Celtics after hitting the Celtics' Jae Crowder in the face early in the third quarter.

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With Cleveland holding a 21-point lead coming out of intermission, Boston's Brandon Bass attempted to work in the post against the defense of the Cavs' Tristan Thompson. As Bass backed Thompson down, Crowder barreled down the paint, looking to establish rebounding position. He crashed into Smith, who looked to anchor down and box out. Crowder responding by leaning on Smith's shoulder blades with his right forearm.

Smith responded by rearing back and swinging his right arm backward, clocking Crowder right on the jaw. Crowder crumpled to the floor following the punch, with his left knee trapped underneath him; as he lay on the hardwood, he reached for his left leg in pain.

After reviewing the play, the referees deeming Smith's swing to constitute "unnecessary and excessive" contact, meriting a flagrant foul-2 and an automatic ejection. He finished with eight points on 3-for-8 shooting and two steals.

After clearing the cobwebs, Crowder was helped to the locker room by teammates and trainers, jawing with the Cavaliers bench as he made his way off the court. He would be diagnosed with a left knee sprain and ruled out of the game. Crowder finished with seven points on 2-for-4 shooting, three rebounds and one assist in his first start of the series, taking the place of guard Marcus Smart as Boston head coach Brad Stevens looked to open the game with a bigger, stronger defensive option on LeBron James.

Smith's shot on Crowder comes two years to the day after he was ejected from Game 3 of the New York Knicks' 2013 playoff series with the Celtics after swinging an elbow into the jaw of then-Celtic Jason Terry. Smith received a one-game suspension for that blow, and performed miserably for the Knicks after his suspension. Whether similar discipline — and similar subsequent struggles — lie in Smith's future remain to be seen.

The square-off with Smith represented the second skirmish of the day for Crowder, Boston's feistiest defender and leading physical presence. Late in the second quarter, after Crowder gave Cavs swingman Iman Shumpert a shot going up the court on the previous play, he found himself on the receiving end of a stiff and very illegal screen from sparingly used Cleveland center — and former Celtics enforcer — Kendrick Perkins:

Under the guise of setting a pick for James, Perkins basically just body-blocked/shoved Crowder to the ground. When Crowder got up and let Perkins know he didn't appreciate it, Perk responded by getting his hands up in Crowder's face; it wasn't quite a punch, but it certainly could have been construed as one, given the clear intent to snuff Crowder and incite further physicality.

Instead, relatively little came of the scuffle:

Perkins was allowed to stay in the game and Crowder missed both of his flagrant free throws.

The Smith-Crowder and Perkins-Crowder altercations, and the animus that might have precipitated them, came after Cavaliers power forward Kevin Love was ruled out for the game following a left shoulder injury suffered after Celtics center Kelly Olynyk locked onto Love's arm during a first-quarter scramble for a rebound. An already pitched atmosphere in Boston, as the Celtics look to stave off elimination and Cleveland attempts to finish off the sweep, became even more fevered after that, resulting in some ugly incidents and even uglier basketball.

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Dan Devine is an editor for Ball Don't Lie on Yahoo Sports. Have a tip? Email him at devine@yahoo-inc.com or follow him on Twitter!

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