Cricket's ball-tracking technology has been placed in the spotlight after it went missing twice during player referrals in the past week.
Australian batsman Ben McDermott was unable to overturn an lbw decision in Tuesday's win over Pakistan after the technology was unavailable for the ball he was given out.
It comes after a Mitchell Starc review was also turned down last Friday against Sri Lanka, when the tracking technology was unavailable at the MCG.
Both decisions would likely have stuck with the on-field call on close inspection, but still brought into question the reliability of the system for the Test summer.
The technology is managed through the host broadcasters, and tracking was regularly available on replays of other balls and analysis in both games on Fox Cricket.
"It's a bit different, I haven't really experienced it before," Australian star Steve Smith, who was at the other end when McDermott was given out, said.
"There's been a few times when we're out in the middle when the umpires will come to the captain and the batters and say the ball tracking is out.
"But they haven't (on these occasions). I don't know whether they've known, or haven't known until they've actually gone up."
Officials are, however, confident the problem is not systematic.
It's believed the issue in Melbourne arose because the match was played on a pitch wide of the square, causing issues with the placement of cameras for the technology.
The Boxing Day Test will be played on the centre strip, while technology will be in place for next year's Twenty20 World Cup.
Meanwhile, it's understood Tuesday night's issue was a case of an isolated human error, with the tracking for that delivery being accidentally erased.
Australia did not lose a review in either of the instances.
Australian Associated Press