England collapsed to 11-2 after Joe Root and Trott, out for a duck, fell to successive Mitchell Starc deliveries.
Root chose not to challenge his decision. Next ball, Pakistani on-field umpire Aleem Dar gave Trott not out in reply to Australia’s lbw appeal.
Australia challenged his decision and third umpire Marais Erasmus overturned Dar’s original verdict despite the fact the side-on Hot Spot image of the dismissal, which might have confirmed whether Trott had in fact edged the ball first, was not available.
Host broadcaster Sky explained the Hot Spot camera missed the Trott wicket as it was replaying Root’s exit a ball earlier. Meanwhile the inventor of the Hot Spot system apologised for an “operator error”.
“It was operator error. My operator did not trigger the system in order to cater for the Trott delivery,” Warren Brennan was quoted as saying by ESPNcricinfo.