First off, your samples need to be gathered from a wide area if they are to be representative - in other words, to meet the "goal" of certifying Mars as biologically safe for human exploration. Travel over a wide area requires long range rovers, and these require artificially intelligent robotic vision systems and autonomous control.

Two, the robotic arm control required to load the samples will require - guess what - artificially intelligent robotic vision systems and autonomous control. You can't do the robotic arm fine work with the telecommunication delays that exist between Earth and Mars.

Given what I see of US work at JPL, Carnegie, and elsewhere, my good friend Dr. Usikov's world wide lock on these continues - though Japan and France may be contenders when the time comes for the downselects.

now back to my own work -
ep

If no one understands that now, they will after the next couple of remotely controlled rovers