Brisbane:Australia coach Tim Nielsen is concerned that a challenge system on umpiring decisions will slow down Test matches.
The International Cricket Council will trial a tennis-like system of allowing each team three challenges per innings of a test, and extend the TV umpire's jurisdiction to use video replay technology to help decide leg-before-wicket decisions.
Nielsen said that the use of technology like Hawk-Eye, which is used in the challenge system in tennis and by TV analysts in cricket, was prone to be overused.
"I just hope they don't get too silly with it," Nielsen told reporters. "We need to be a bit careful that we don't jump headfirst in and go gung-ho the other way and make too many calls.
"It means almost one-third of the (10) wickets that you need to get a team out, you can contest, which seems like a high number to me."
Under the ICC plan, only the captains of the batting and bowling teams can challenge decisions, with on-field umpires then consulting with the third umpire or TV umpire before making the final decision on a dismissal.
"I just hope that we don't have big stoppages and regular conjecture about umpiring decisions on the back of technology being introduced," Nielsen said.
"If it's going to work, it's got to make the game better."
The ICC's cricket committee ruled the challenges on LBW decisions referred to the third umpire could be determined with the use of Hawk-Eye, but only for the video replay of where the ball hit the batsman, and not the predicted trajectory technology used in TV analysis which shows whether the ball would have hit the stumps.
TV umpires can already adjudicate on line-ball decisions like run outs and stumpings using video replays.
Top-ranked Australia leaves for the West Indies on Saturday but that series will not be subject to the new challenge system, which could be introduced when England hosts South Africa.
Brad Haddin, who is set to replace retired long-term wicketkeeper Adam Gilchrist in the Australian test lineup, would prefer to see the decisions left to the on-field umpires.
"I like the umpiring set-up the way it is, you take the good with the bad," he said. "I like that human element about it."
The ICC challenge system proposal comes in the wake of its decision to remove veteran West Indian umpire Steve Bucknor from a series between Australia and India in January after two poor decisions that contributed to India's losing the match and falling behind 2-0 in the four-match series.
India threatened to withdraw from the tour unless Bucknor was removed from the third test and a ban on its off-spinner Harbhajan Singh for making an alleged racist comment to an Australian player was overturned.
The ICC pulled Bucknor from the next match and an appeals panel overturned the three-match ban on Harbhajan. India won the third match but lost the series 2-1.