Despite the past few years of misery in form at home to the Royals the Blades ticket office is selling fast and expect a crowed of over 20,000 to attend.
United drew their last game on Tuesday night at home to Stoke City 0-0 but failed to take take control when Gifton Noel-Williams was given his matching orders.
On the injury list is Paul Thirlwell (groin), who has yet to make his debut for the Bramall Lane club and is expected to be out for another two weeks.
Defender Simon Francis is also out, he has to recover from tonsillitis before his ankle injury, also Billy Sharp is sidelined with Shingles.
Meanwhile Alan Quinn, Ashley Ward and Jonathan Forte are all expected to play some part in the game, all impressed after coming off the subs bench against Stoke.
Teddy Sherringham's late goal for West Ham United was enough to secure a 1-0 win over Reading on Tuesday night at Upton Park and the Royals will be keen to get back to winning ways.
They will however have to make the trip up North without Glenn Little after suffering a hamstring injury against the Hammers and is expected to be out for two weeks. Summer signing Bobby Convey from DC United is expected to make his full debut in place of injured Little.
Midfielder James Harper remains touch and go after suffering a injury at Upton Park but the Madejski Stadium club remain hopeful he will make a full recovery.