Australian Test skipper Tim Paine has questioned the decision review system, saying it has been "frustrating" to deal with the technology that is "not a perfect system".
Australia endured some frustrating moments during their 31-run loss to India in first Test when a few decisions went against the hosts after reviewing the umpires calls.
Umpire Nigel Llong had given Ajinkya Rahane out caught at bat-pad for 17 early on Sunday but the decision was overturned on review when replays indicated that the ball had hit the batsman's front pad outside the line of off stump and missed his bat and gloves.
Similarly, Cheteshwar Pujara, who had scored a gritty 123 in the first innings, was adjudged out on eight and 17 to Lyon on Saturday but the dismissals were overturned.
Replays found no contact with bat or gloves in his first dismissal and the second one was overruled as ball tracking suggested that the ball would have gone over the bails.
"Look, it's (DRS) not a perfect system and I haven't got the answers. It's just frustrating, I'd imagine it's frustrating for everyone. But it is what it is," Paine was quoted as saying in the 'Sydney Morning Herald'.
The Australian skipper initially said the calls had been "interesting," then when later asked why DRS was interesting, he said: "I think everything. I don't want to talk about DRS. It's just - it is what it is.
"A lot of balls seem to be going over the top of the stumps, I know that, that live don't look like they are. So yeah, it is what it is."
(with news agency inputs)