Paul Ifill struck a superb 20-yard goal to inflict only a second defeat in 18 games on Sheffield United.

Millwall's winner came after 63 minutes when veteran striker Steve Claridge picked the ball up on the left.

He fed Ifill, who strode forward to hit a rasping drive low past goalkeeper Paddy Kenny and into the corner of the net.

The goal was just about deserved for Millwall, who had been profligate with their shooting and rarely made Kenny work despite peppering the visitors' goal with shots and headers.

The result stretched their unbeaten run to six games and maintained their position among a host of teams bidding for a play-off spot.

Blades boss Warnock threw on two fresh strikers in Steve Kabba and Wayne Allison as soon as Millwall scored.

Missed chances

Former Crystal Palace frontman Kabba was soon in the thick of the action, volleying over as United went in search of a quick equaliser.

Michael Tonge also went close when his shot was saved by Millwall goalkeeper Tony Warner.

United had begun the game well with chances falling to both Australian centre-back Shaun Murphy and Michael Brown.

Millwall got their first sight of goal in the 17th minute, but Murphy blocked a close-range effort from 18-year-old Scot Peter Sweeney, making his first full start for the club.

At the other end, Robert Ryan's left-foot volley just cleared the crossbar.

In the second half, Millwall had more chances when David Livermore fired a 25-yard shot wide and substitute Christophe Kinet volleyed over with Kenny a spectator.

Then Paul Robinson got his head to Kinet's far-post corner but knocked the ball wide, before Ifill stepped in with the decisive strike.

Millwall: Warner, Lawrence, Ward, Robinson, Ryan, Ifill, Wise, Livermore, Hearn, Sweeney, Claridge. Subs: Gueret, Kinet, Bull, Braniff, Baltacha.

Sheff Utd: Kenny, Kozluk, Murphy, Jagielka, Quinn, Ndlovu, Brown, McCall, Tonge, Windass, Mooney. Subs: Peschisolido, Allison, Kabba, Thompson, Edghill.

Referee: B Curson (Leicestershire).