Ray Allen is the NBA's all-time leader in three-pointers made, but in these playoffs, he is shooting just 26 percent from downtown. His ankle injury has been preventing him from being himself, and at this point, it's depressing to watch.
Opponents realize it too, which is also depressing. Consider how Shane Battier guarded this play. As you can see here, he's more concerned with defending Kevin Garnett at the free-throw line than Allen from beyond the arc. He's not even looking at Allen here.
Allen therefore popped open for three, but he missed. It's amazing how little respect Battier is paying to him.