Sydney match umpires lodged reviews for three catches taken low to the ground in the slips at the SCG. On each occasion, third umpire Kettleborough found evidence the ball had touched the ground before the fielder was able to control it. Consequently, none of the catches were given.

"I don't really know the answers but there has to be a way to try and improve it somehow," Cummins said after the Test against South Africa ended in a draw. "As it currently stands, it's really hard to give a batter out. If there's any kind of benefit of the doubt, it goes the batter's way.

"I think with a couple of camera angles really slowed down, it's pretty hard to not find doubt somewhere. I do feel for Ketts a little bit up there."

In making a decision, the third umpire only has access to footage from the host broadcaster, Fox Sports and not from Seven Network cameras.

"Maybe there's more cameras we can use down the track," Cummins said.

"The way the umpires conducted the three was pretty good. I think it was brilliant," he said. "Once you've set the bar with the first one, you can't really budge much from there.

"Those things are always going to be a grey area, some guys will say out, some guys will say not out. At the end of the day, their decision is final and as players we respect that."