You see this move all the time — a shooter is about to take three from in front of the opposing bench so one of the players on that bench yells to try and distract the shooter. Actually, Vinny Del Negro does that pretty often, and it’s kind of embarrassing when a coach does it, but I get why players do it.
Tony Allen never stops playing defense, even when he’s sitting on the bench — notice he is up and standing in position to distract the shooter before the pass even arrives, he’s that good — so he tried to get in Derek Fisher’s head by yelling and waiving a towel behind him. But he didn’t mean to accidentally throw his warm-up shirt on to the court at the same time.
Fisher missed the three (he was 3-of-11 on the night from deep) but the refs correctly awarded him the three points and called a technical on Allen for the play. Kevin Durant hits the shot, it’s a four-point play. He doesn’t fight it, in fact you can tell he’s pretty embarrassed by it.
Allen can laugh about it now because the Grizzlies held on for the win and advance on to the conference finals where they likely take on the Spurs (not exactly David Stern’s dream TV matchup).