I’m watching the Barclays World Tour Finals as much as I can and I saw something interesting during the Llodra-Zimonjic/Bopanna-Qureshi doubles match. Bopanna hit a lob that went up through the overhead scoreboard (think Jumbo-tron). Zimonjic thought they won the point and yelled, but the ball fell inside the lines. Bopanna and Qureshi stopped playing after hearing Zimonjic yell and were upset with the chair official for deciding to replay the point based on an “involuntary hindrance.”
After watching the video, please comment on whether or not you agree with the call.
Pacific Northwest Tennis Officials Association 
I was confused when I first saw this point during the year-end championships. After watching a replay a few times (I love watching tennis on TiVo) I decided that Lars Graf’s ruling to replay the point might have been correct. I believe the “involuntary hindrance” was due to the fact that the ball disappeared above the scoreboard and no one could tell whether or not it had made contact with any permanent fixture. The hindrance was due to the fact that everyone lost sight of the ball and it was involuntary because it was not due to any deliberate action on the part of any of the players. The yell by Zimonjic was secondary to the fact that the ball disappeared. The only problem with the outcome was that Lars did not explain his call at all well.
When I first saw the point at the time, I believed it was an intentional hinderance, loss of point based on the simple rule that a player who shouts out during a point, does so voluntarily (barring the bee sting scenario), but 820dough makes ann excellent point. I think you would have to have been there, to understand exactly what the circumstance was. Its not a situation that most umpires will ever have faced, since the arena where it occurred is unlike any that most of us will ever work in. I wonder if the possibility of balls going up to the roof and being lost from sight was discussed by officials before hand.