Matthew Wade has asked whether DRS has been implemented consistently during the MCG Boxing Day Test, after Tim Paine was given out on the third day. Paine was ruled caught behind off Ravindra Jadeja after the on-field call by Paul Reiffel was overturned by third umpire Paul Wilson. Paine, who was the beneficiary of a borderline run-out call in the first innings, was clearly unhappy with the decision as he left the field.

The decision was made based purely on a Snicko spike after there was no mark on Hot Spot - which is the correct protocol - but Wade drew a comparison with Australia's review against Cheteshwar Pujara to the first ball of the second day's play. Then, too, there was no mark on Hot Spot and a very small spike on Snicko, although on that occasion there was a suggestion the toe of Pujara's bat had clipped his pad.

"From what I've seen it looked pretty similar to the first ball of yesterday, the one we actually referred, I think it was off Pujara," Wade said. "So from all reports and what I've seen, Snicko showed a very similar thing, one was given out and one was not out. That's the way the cookie crumbles sometimes, but that's what it looked like from where we've been sitting and watching.

"I heard a noise on the Pujara one, I was at first slip at the time, and his bat was the only thing out there, and then we saw what you guys saw on the ground, which was a small spike. Either way if it was out or not out, consistency is all you want as a player."

Channel Seven has former ICC umpire Simon Taufel on their panel as part of their coverage for the series, and he explained the decision-making process moments after the Paine dismissal.

"There's a number of things the third umpire is working through under his conclusive evidence protocols," he said. "The first thing is, is there a deviation? That's normally the first thing they look for. The second thing is, if there's no deviation apparent, the redundancy in the protocol looks at the Hot Spot, and if there's no Hot Spot they can determine as conclusive then the further protocol is to go to RTS.

"If the ball is next to the bat while there is a spike, as the ball goes past the bat, or up to one frame past the bat, that is deemed to be conclusive evidence that the ball has hit the bat."

Expanding on the point about the spike being evident one frame past the bat, Taufel added: "Every morning the technician, as part of the match officials' team, will go through and do an audio calibration as best they can to line up sight and sound. But light does travel faster than sound and that's why there's that little bit of timing difference."

The use of Snicko to effectively over-rule Hot Spot has been in place since the 2013-14 Ashes in Australia. "If there's a mark on Hot Spot he'll go straight to out. That's his conclusive evidence straight away," Geoff Allardice, the ICC's head of cricket operations, had said at the time. "The only time Snicko will be used is if there's no mark on Hot Spot."

That does, effectively, mean the system could be used without Hot Spot but that technology can be useful for confirming point of contact when bat and pad are close together which can often be seen with lbw appeals, for example. There was also a dismissal earlier in Australia's second innings, when Joe Burns was caught behind and reviewed the decision, which produced a clear mark on Hot Spot and Snicko was not used before confirming Burns was out.