Brad Stevens has not been pleased with the new rule allowing coach challenges. The Boston Celtics head coach appeared to get caught cursing on camera during Boston's game against the New York Knicks on Sunday afternoon:

Stevens had a lighthearted moment with respect to the incident, claiming the footage was “digitally edited.” Naturally, Stevens would take it this route given his calm demeanor and roots in faith:

The challenge is in its first year of implementation in the NBA, but it has been a frustrating mess for coaches.

Stevens technically won the challenge in question. The Celtics were up nine over the Knicks with just a few minutes to play, but Julius Randle was headed to the line for the final part of an and-one after drawing the hoop plus the harm against Celtics forward Grant Williams.

The replays showed that Williams was in position when Randle barreled into him, and thus the refs changed the call and did not award Randle with a free throw. However, Stevens' frustration stems from the decision not to call a charge on Randle and still award him the bucket.

Stevens is hardly the only coach to complain about the new rules. Los Angeles Clippers head coach Doc Rivers blasted the challenge system during the preseason:

There is a very real possibility that both the NBA and the NFL–which now allows challenges on pass interference calls–could do away with these new rules almost immediately.

Just don't expect Stevens to openly admit to using vulgarity to express his own frustration.

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