The match takes place at the Nelson Mandela Bay Stadium and kickoff is at 8pm.
The defending champions are not playing badly, but two points out of a possible six in their last two games is hardly the form that will threaten Absa Premiership log leaders Kaizer Chiefs.
Bucs coach Roger de Sa knows they can't afford to drop points in the manner that they did at Chippa United last week if they want to go into the Christmas break the merrier of the Soweto giants.
Though they trail Chiefs by three points, Pirates are unbeaten in eight league games, a run last witnessed when they made a charge for the title last season. The signs are ominous.
Last weekend's Soweto derby, which ended 1-1, showed how close the margins were between the top two teams in the standings but fourth-placed Maritzburg could have a big say in determining who holds the lead at the halfway mark with a solid performance tonight.
"We have forgotten about the draw against Chiefs," Bafana and Bucs winger Sifiso Myeni said this week. "It is back to business for us as we prepare for the match against Maritzburg. They are a tough side and I think we will need to be at our best to defeat them.
"We are desperate to win this match so that we can continue closing the gap at the top."
Myeni's trickery plus Daine Klate's service, and Collins Mbesuma's bullish finishing will be up against Ernst Middendorp's defence-reliant counterattacking tactics.
The miserly German is expected to give defensive midfielder Ruben Cloete instructions to mow down anyone in black and white who advances into dangerous areas.
United have lost two games in a row - to the other "surprise package" Platinum Stars and strugglers Ajax Cape Town.