United's play-off dream remains alive following a battling and deserved point on the first visit to Cardiff City's new home.
Stephen Quinn's second half close-range effort earned the Blades a second successive point on the road after an unstoppable Jay Bothroyd effort gave Cardiff the lead.
With his playing squad ravaged further by injuries, chief Blackwell was forced into three more changes for the visit to South Wales. Taylor, Bartley and Little took the places of Seip, Yeates and Camara, whilst the Blades could again only name just six substitutes.
Cresswell was the only fit striker available to United's management and, understandably, he started alone in attack, backed by a five-man midfield.
For the third encounter in succession, United won a corner within the opening minute but Little's delivery was collected by Marshall and Cardiff began their first move of the game. With less than 100 seconds gone, Bothroyd collected the ball in his own half, beat three and, after cutting in from the right, powered in a shot which was just wide.
United's Connolly was the first to be booked, for a late sliding tackle on Capaldi, and the resulting free-kick from McCormack needed saving by Simonsen, low to his right.
McCormack was heavily involved early on but had his weak penalty appeal turned away, although he did win a free-kick in a dangerous position when blocked off by Nosworthy, who was shown a yellow card. From the set-piece, Bothroyd's powerful shot was held at the second attempt by Simonsen.
Cardiff had made the better start and Taylor had to cover when McCormack looked like getting in once again and Simonsen was forced into yet another save on 15 minutes, pushing away a speculative effort from Whittingham.
United's first serious chance, on 18 minutes, was the result of an error in the Cardiff back line but Little, cutting in from the right, saw his shot comfortably saved by Marshall. The early onslaught complete, the home crowd were quietened but Bothroyd and McCormack were a constant threat.
As the half wore on, Blackwell would have been relatively happy that Cardiff's attempts had been limited but the good defensive work was undone just before the break with an unstoppable strike.
With the clock just about to tick around to 45 minutes, Cardiff's Quinn floated a ball to the edge of the penalty and Bartley's attempted clearance could only find BOTHROYD, who unleashed a 25-yard shot that flew beyond Simonsen's reach into the top corner.
Just two additional minutes gave the Blades little time to respond and with few attacking options to call from the bench, the same XI took to the field for the second period.
Simonsen had to be alert to catch a back header from Stewart soon after the interval and the United goalkeeper was flattened by a Blake challenge which earned the defender a booking.
Harper tried his luck from 25 yards but couldn't repeat the strike at Doncaster and there were appeals from the Unitedites in the crowd for a penalty when Taylor's cross struck Gyepes.
United's Quinn was harshly booked for preventing a quick Cardiff free-kick, which was being taken from the wrong place and Bothroyd was also cautioned, for diving in the penalty area. The home side came close to adding a second but Simonsen was ideally placed to collect Burke's shot on 61 minutes and Bothroyd failed to get on the end of Whittingham's cross soon after.
Blackwell's first change was introducing Yeates for Stewart and it took just two minutes to pay off. The substitute began in a central role with Quinn being edged out to the left, which was instrumental in the equalising goal.
With 67 minutes gone, Yeates, drifting to the right, delivered a cross which saw QUINN get ahead of his marker at the back post and although the initial prod was blocked by the goalkeeper, the Irishman followed up to squeeze home the rebound.
Within a minute Cardiff could have regained the lead, but for some impressive defending. Burke's deep cross found McCormack but the faintest of touches from the sprawling Simonsen was enough to prevent the ball crossing the line and Bartley cleared the danger.
After firing a shot at Marshall, Yeates was moved out to the right flank to accommodate Williamson, who replaced the tiring Little, whilst United were forcing the home side on to the back foot.
Cardiff's response was to bring on Chopra for the final ten minutes and he struck the top of the United crossbar within minutes of being introduced with a shot from 20 yards.
Taylor was cautioned for a foul on Burke and when four minutes of additional time was announced, Blackwell handed a debut to Lowton, replacing Taylor.
Nosworthy and Bartley both showed their mettle with late clearances and Williamson was cautioned. There was late drama with a Cardiff free-kick but the Blades repelled once again - thanks to an important Lowton block - and a point, in the circumstances, was commendable.
Cardiff: Marshall, Rae, Gyepes, Whittingham, Bothroyd, McPhail, Burke, Capaldi, Quinn, Blake, McCormack (Chopra 82).
Unused: Enckelman, Etuhu, Taiwo, Feeney, Matthews, Wildig.
Blades: Simonsen, Montgomery, Nosworthy, Harper, Taylor (Lowton 90), Cresswell, Stewart (Yeates 65), Bartley, Little (Williamson 71), Quinn, Connolly.
Unused: Bennett, Seip, Fortune.












