Sheffield United staged a magnificent come back to share the spoils in a thrilling 3-3 draw at Prenton Park tonight.

A Simon Tracey error in the 11th minute gifted Tranmere midfielder Liam O'Brien the opener but the Blades restored parity when Wayne Quinn hit home eight minutes after the break.

But United's play-off ambitions appeared to be in tatters when they were left reeling by a devastating two-minute blitz by the home side.

In the 64th minute Gary Jones restored Rovers lead with a perfect header. And Tranmere's 18-year-old striker Andy Parkinson curled a goal fit to grace the World Cup this summer beyond Tracey two minutes later.

But the First Division play-off hopefuls refused to surrender. And 12 minutes from time Dean Saunders headed Paul Devlin's cross beyond Steve Simonsen to set up an enthralling finale.

Rovers held back the Blades pressure but in the dying minutes Welsh international Saunders returned Devlin's favour and the former Birmingham man drilled home a priceless equaliser.

The home side had enjoyed a relatively comfortable first half against a side 10 places above them in the First Division.

The Blades never really discovered their true form in the first period as manager Steve Thompson's sweeping changes to the side which lost 4-2 to West Brom on Saturday failed to ignite.

But in the 10th minute the Blades could have taken the lead when captain David Holdsworth spurned two golden opportunities.

Quinn swung over a perfect corner to the head of the central defender who could only watch astonished as Dairusz Kubicki cleared off the line.

The rebound fell to the feet of the Blades captain but his shot was weak and straight at Simonsen.

The subsequent clearance found John Morrissey clear on the right and he linked with youngster Parkinson before allowing Kubicki to send over a cross from the byline.

Tracey, in his first game since February and replacing the injured Alan Kelly, dropped the ball and O'Brien pounced.

Then eight minutes after the break the Blades enjoyed their own slice of luck. With no pressure on him Rovers defender John McGreal failed to control the ball, leaving Nicky Marker time to pass to midfielder Graham Stuart. The former Everton man found Quinn 12 yards out and the full-back latched onto the ball before hitting home his second of the season.

But then the home side hit back in devastating fashion. In the 66th minute Morrissey crossed deep from the right wing and while falling backwards striker Gary Jones still managed to guide his header beyond Tracey's outstretched right hand.

Just two minutes later Parkinson produced the kind of skill his manager would pair over.

With little or nothing on the 18-year-old also had defenders Lee Sandford and Chris Wilder to get past from his position on the left hand edge of the area.

But the 18-year-old curled a perfect ball with the outside of his foot beyond Tracey for only his first ever League goal.

The Blades were not going to be beaten, though, and 12 minutes from time Devlin crossed for Welsh International Saunders to nod home from close range.

Then in the final minute the comeback was complete when Saunders charged into the area to reach the byline.

He swung back across for his previous provider Devlin who hit home a priceless equaliser from 10 yards.

Tranmere: Simonsen, Kubicki, Thompson, McGreal, Hill (Mahon 81), Parkinson, Morrissey, Mellon, G. Jones, O'Brien, L. Jones (Irons 63).

Subs Not Used: Morgan.

Goals: O'Brien 10, G. Jones 64, Parkinson 66.

Sheff Utd: Tracey, Wilder (Morris 85), Quinn, Nilsen, Holdsworth, Sandford, Saunders, Marker (Marcello 63), Devlin, Hamilton, Stuart.

Subs Not Used: Dellas.

Goals: Quinn 52, Saunders 78, Devlin 90.

Att: 7,526

Ref: T Heilbron (Newton Aycliffe).