In the 12th over of Australia’s second innings in the Sydney Test when replays of India’s appeal for LBW against Steve Smith off an R Ashwin delivery showed a mysterious fourth stump. There was an uproar on social media. “Have we heard any clarification from the authorities responsible for this? The mysterious fourth stump making an appearance on replays (sic),” Aakash Chopra had wondered in a Twitter post. The Indians thought it was out and referred. DRS said ‘umpire’s call’ an LBW appeal against Steve Smith in the second innings had been reviewed by the bowling side after the onfield umpire ruled in favour of the batsman. In the replays, a fourth stump had surfaced ‘mysteriously’ on the screen. The operators of the Decision Review System (DRS) have now admitted the gaffe.
Taylor explained how and why it happened. “We tracked the ball normally in our tracking system and it showed it missing the stumps. For the DRS the next step is to play the ball track back, superimposed over the ‘end on’ broadcast TV camera when the 3rd umpire calls for it. At the start of play we calibrate the two TV cameras at each end of the pitch to ensure they are perfectly aligned when we play our ball track over the live camera. When we did that, before going to air, it was fine and the ball was clearly missing.
“Just before we were going to replay, the end-on camera lost focus for an instant and when that happens it loses its calibration and we have to recalibrate. It happens a few times during the day but this was the first time it had ever happened between the time we tracked the ball and the time we had to replay it.
“Our operator went through the recalibration programme to realign the camera — he thought he had successfully done that but as soon as he replayed the video with the track on it, he realised that it hadn’t recalibrated correctly because the ball was now clipping the stump rather than missing it.