Match referee Jeff Crowe sought to extinguish Monday the smouldering Ashes catching row which became one of the major talking points during England's second Test victory over Australia here at Lord's.
The replays were inconclusive and Bopara was allowed to continue his innings.
The batsman started to walk off the field but was told to stay put by Australia captain Ricky Ponting.
However, this time there was no referral with South Africa's Koertzen and West Indies' Doctrove deciding Hughes was out without calling in English official Llong, even though replays again made it seem uncertain if the catch had been taken cleanly.
International Cricket Council (ICC) Test-match playing regulation state "the umpire at the bowler's end shall be entitled to refer an appeal for a caught decision to the third umpire if both he and the square-leg umpire are unable to decide whether a catch was taken cleanly".
Crowe, explaining the difference between the two incidents, said in an ICC statement: "In the first instance, when Nathan Hauritz was the fielder, the on-field umpires consulted and neither was able to decide if the catch was taken cleanly so they referred the decision to the third umpire.
"However, in the second instance, when Andrew Strauss was the fielder, the square-leg umpire (Doctrove) was confident the catch was taken cleanly and so did not refer it to the third umpire," former New Zealand captain Crowe added.
"There has been some confusion as to why one incident was referred and not the other so it is simply a question of whether either on-field umpire is able to make the call himself or if he needs advice from the third umpire.
"If he is confident of the decision then he will make it himself regardless of how near or far away the incident took place," explained Crowe.
Australia coach Tim Nielsen was clearly unhappy Llong had not been called in to rule on Hughes's dismissal, saying after stumps on Sunday: "I would have liked to have seen it go to the third umpire from a consistency point of view."
England won the second Test by 115 runs on Monday to take a 1-0 lead in the five-match series, following a drawn opener in Cardiff, as they looked to regain the Ashes.
The third Test starts at Edgbaston on July 30.
Source: AFP Global Edition