Centre Roberts, who went off concussed after being knocked out following a clash of heads in the first-half of the 26-12 loss to Argentina, hopes to be involved.
And if he successfully comes through the necessary medical-related protocols, he is likely to feature in Wales' starting line-up when it is announced later today.
"We let the Welsh public down on Saturday, and the players are well aware of that," Roberts said.
"To have a six-day turnaround and to play against a team like Samoa is a great opportunity to put things right."
Interim head coach Rob Howley's line-up will feature a minimum of two changes, given that lock Alun-Wyn Jones (shoulder) and flanker Josh Turnbull (knee ligaments) have been ruled out of remaining autumn Tests with Samoa, New Zealand and Australia.
Luke Charteris and Ryan Jones are the likely replacements, while there could also be opportunities for fly-half Dan Biggar and hooker Richard Hibbard as Wales target a first victory since beating the Barbarians over five months ago.
Pumas make three changes
Argentina have made three changes to face France in Lille on Saturday, two enforced by injuries to Felipe Contepomi and Juan Martin Hernandez in last weekend's win over Wales.
Marcelo Bosch, ever-present during the Rugby Championship, joins Gonzalo Tiesi in the centre in place of Contepomi, whose knee ligament injury has ruled him out for the rest of the tour.
Lucas Gonzalez Amorosino comes in at full-back for Hernandez, who is recovering from leg muscle fatigue but could be fit for the November 24 Test against Ireland in Dublin.
And Horacio Agulla lines up on the right wing in place of Gonzalo Camacho, who is rested but has a place on the bench.