But the most telling contribution came from visiting goalkeeper Paddy Kenny who gifted the home side the initiative on the stroke of half-time.
The Blades had taken the lead on 25 minutes through a Peter Ndlovu volley but Kenny met Richard Langley's tame free-kick with disastrous consequences, allowing it to creep under his body for the equaliser.
The visitors almost opened the scoring on six minutes, after Michael Tonge had beaten Langley on the right wing. Tonge ran to the byline before pulling the ball back for Jack Lester but the Blades' top scorer side-footed into the side-netting from six yards.
Cardiff midfielder Gareth Whalley then caused United all sorts of problems at the back. First his right-wing free-kick was deflected into the net but the goal was rightly disallowed for handball by Alan Lee.
On 19 minutes Whalley's left-footed corner was turned inches wide by visiting defender Phil Jagielka, then Whalley crossed for Robert Earnshaw, whose glanced header forced Kenny to tip over.
But all that pressure came to nothing as the visitors took the lead on 25 minutes. Tonge's right-wing corner was headed clear by Tony Vidmar to Ndlovu, who was unmarked on the edge of the box.
Ndlovu then unleashed an unstoppable right-foot volley past Martyn Margetson for his first league goal since late September.
Robinson had a long-range effort easily saved but Kenny then made a mess of Langley's 25-yard free-kick in during stoppage time.
For some reason, as the ball bounced in front of the Irish keeper, he tried to palm the ball away with both hands instead of scooping it up, but the ball squirmed over the line.
And he was beaten again as the home side took the lead on 63 minutes through Robinson's well taken half-volley.
Right-back Gary Croft crossed from deep within the United half and Simon Francis headed the ball away from the back post.
But Robinson was lurking just behind the Blades defender and his left-footed strike from the left side of the box went past Stuart McCall and beyond Kenny's reach into the far corner.