BOSTON, MA - MAY 13: JR Smith #5 of the Cleveland Cavaliers reacts from the bench late in the fourth quarter in his teams loss to the Boston Celtics in Game One of the Eastern Conference Finals of the 2018 NBA Playoffs at TD Garden on May 13, 2018 in Boston, Massachusetts. The Boston Celtics defeated the Cleveland Cavaliers 108-83.

Watch: Celtics fans chant 'F--- you J.R.' after cheap shot against Al Horford

Maddie Meyer / Getty Images Sport / Getty

Jr Smith shoves Al Horford in the air, Marcus Smart ain't havin' it pic.twitter.com/WBHEgqATjj
— Born Salty (@cjzero) May 16, 2018

Boston Celtics fans were rightfully furious with Cleveland Cavaliers shooting guard J.R. Smith after he gave a dirty foul by pushing Al Horford in the back while he was airborne.

Smith received a flagrant-1 on the play and an additional technical foul after being confronted by Marcus Smart.

He was also treated to an obscene chant from Celtics fans.

"Fuck you, JR" chant in the Garden pic.twitter.com/3tX8Ihb0u7
— gifdsports (@gifdsports) May 16, 2018