Arnason picked up a 10th yellow card of the season in Wednesday’s 2-0 defeat at Nottingham Forest and will now serve a two-match ban.
Boss Steve Evans will be without Jack Hunt at right-back after he picked up a hip injury at Forest so either Frazer Richardson or new signing Lawrie Wilson will come in.
Danny Ward should offer some better news to the Millers as he is set to return to the squad after missing the last three games with a foot injury while Evans was also trying to bring a goalkeeper in on loan ahead of the clash.
Sheffield Wednesday’s new loan signing Lloyd Isgrove will be included in the squad.
Isgrove joined the club from Southampton until the end of the season this week and could start as boss Stuart Gray still has a lengthy injury list.
Strikers Will Keane (ankle) and Sergiu Bus (groin), midfielder Jose Semedo (foot), plus defenders Glenn Loovens (foot) and Kamil Zayatte all remain sidelined, while Liam Palmer (ankle) has been ruled out for the rest of the season.
Striker Caolan Lavery is pushing for a start. He stepped off the bench during the midweek defeat at Wolves after recently being recalled from his loan spell at Chesterfield.