Two former Australian cricket umpires think the standard of umpiring has declined since the introduction of the controversial Decision Review System. They say it is undermining umpires' confidence, making them lazy and ruining their technique.
But former NRL referees boss Bill Harrigan says modern technology is an essential part of modern sport because ''people demand perfection''.
The introduction of technology was seen as a panacea for all umpiring errors and has been brought into cricket, both rugby codes, AFL, tennis and will soon be a part of football.
Former umpire Ross Emerson.
Cricket's DRS has been in the spotlight for the entire Ashes series, following repeated errors by the umpires on the field as well as the third umpire.
Clear-cut catches have been given not out, and the inconsistent use of trajectory-modelling-system Hawk-Eye to determine leg-before-wicket decisions has many scratching their heads, with balls shown to hit the stumps still resulting in not-out decisions.
Now, Hot Spot, which uses infrared cameras to determine whether a batsman has hit the ball, has also come under fire after missing several faint edges, as well as silicone tape allegedly being used to deceive it.
Calls for the removal of DRS are getting louder, with former England players Andrew Flintoff and Michael Vaughan among those who have condemned it.
Former Australian umpires Dick French and Ross Emerson have expressed concern with the use of technology in cricket.
French, who officiated 19 Tests between 1977 and 1987, said he was never in favour of it, while Emerson, who famously called Sri Lanka spinner Muttiah Muralitharan for throwing, said the system should be scrapped unless the International Cricket Council invested in its own, accurate technology.
Both felt the standard of umpiring was being eroded by DRS.
Their solution is simple - invest money in training umpires.
French said umpires used to operate with 95 per cent accuracy before the system was introduced, meaning there was only a small margin for improvement from its use.
The 75-year-old also felt DRS led to the erosion of the umpires' authority, with captains challenging them when they thought they were wrong.
He said overturned decisions affected the umpires' confidence and a reliance on technology ruined their technique.
Umpires no longer needed to get into position to adjudicate run-outs and simply referred them upstairs.
''I've never been in favour of it, whatsoever, I think it takes away the challenge of the umpires to get it right,'' French said.
''It could make them lazy, I'm not saying it does, but it could.
''To my mind it's destroying the very fabric of the game, I just don't like it at all, particularly the LBW projection of the ball.''
Both French and Emerson doubted Hawk-Eye's accuracy, which is backed up by the way it's used with more than half the ball needing to hit the stumps.
Given the radius of a cricket ball is about 3.6 centimetres and the width of the stumps is 22.9 cm, that equates to a 16 per cent margin for error.
Emerson said technology needed to be ''100 per cent'' accurate.
Snicko uses a graph of sound waves in conjunction with video footage to help determine whether a batsman has hit the ball, but it isn't part of the DRS.
Emerson didn't understand why, especially given the inaccuracies of both Hot Spot and Hawk-Eye.
He said when he was umpiring during the '90s, the third umpire was paid half as much as those in the middle.
Now the third umpire has the hardest job of the three officials because all the tough decisions were being referred.
''It's important to get the decisions right, but what's happened with the DRS and the reliance on technology is they've put the cart before the horse,'' Emerson said.
''What they should be doing is trying to improve the standard of the on-field umpires and they don't appear to be doing that.
''With the DRS, the umpires in the field have abrogated their responsibilities and they almost don't care if they make a mistake because it can be corrected, but the technology they're relying on isn't good enough.''
Harrigan, who was the best rugby league referee in the world before retiring, said technology needed to be a part of modern sport, but he wanted officials to back themselves and use it only when they had doubts.
He said it was important to understand mistakes were always going to happen because of the ''human element''.
''It's got to be a part of the game and that's because people demand perfection and the only way to get close to that perfection is to use technology when you have it,'' Harrigan said.
''Although the technology should decrease the amount of mistakes that can be made, we have to accept there's still a human element to it so we'll never get to 100 per cent [accuracy].''