Cardiff had two players sent off in a nightmare first half as Championship promotion rivals Sheffield United cantered to victory at Ninian Park.

David Cotterill fired the Blades ahead from the penalty spot in the 25th minute after Bluebirds defender Gabor Gyepes committed a professional foul on Darius Henderson, for which he was sent off.

The hosts were dealt another massive blow in the 33rd minute when striker Ross McCormack was sent off for a professional foul on Kyle Naughton.

Substitute Jamie Ward headed in a second for the visitors shortly after the restart and Stephen Quinn fired in a third with three minutes remaining.

Cardiff went into the game with an outstanding record of 12 wins and only two defeats at Ninian Park this season, but they met their match in Kevin Blackwell's side.

Victory lifted the Blades to fourth spot but Cardiff should have opened the scoring inside the 10th minute.

Joe Ledley delivered an outswinging corner from the left flank and Gyepes sent his header wide of the mark.

However, the Blades went even closer in the 19th minute when Greg Halford collected possession and hit a right-footed shot which Bluebirds goalkeeper Stuart Taylor was forced to tip around a post.

United began to build momentum and took the lead when Gyepes hauled down Henderson and Cotterill did the rest from 12 yards to claim only his third goal of the season.

In the 27th minute, Cardiff threatened an equaliser when a free-kick from Gavin Rae was met with a firm header by Miguel Comminges which forced Paddy Kenny into a smart stop.

However, the Bluebirds suffered a major setback in the 33rd minute when McCormack was sent off for a professional foul on Naughton.

United quickly went in search of a second goal and Halford shot straight at Taylor before Quinn fired narrowly wide from the edge of the 18-yard box.

In the 39th minute, Cardiff had a half-chance when Rae saw his header blocked by Naughton before Comminges fired wide for Cardiff on the stroke of half-time.

Within seconds of the restart, United sealed the points when Cotterill crossed from the right flank and Ward headed home from six yards out.

Blackwell's men sought to press home their advantage but Quinn's effort in the 58th minute sailed just wide.

Cardiff, to their credit, refused to surrender and Roger Johnson headed a corner from Comminges just wide and then Rae sliced a shot off-target.

United substitute Craig Beattie hit a shot just wide in the 74th minute and was at it again four minutes later with another fine strike that narrowly failed to test Taylor.

The Blades were comfortable and never looked like letting Cardiff back into the game as they played out a victory which lifted them three points above their hosts.

Quinn added the coup de grace in the 87th minute when he took a pass from Beattie and rifled home left-footed from six yards.

Teams:

Cardiff Stuart Taylor, McNaughton, Gyepes, Roger Johnson, Kennedy, Rae, Ledley, Burke (McPhail 31), McCormack, Chopra (Comminges 26), Bothroyd (Eddie Johnson 76).

Subs Not Used: Whittingham, Owusu-Abeyie.

Sent Off: Gyepes (24), McCormack (33).

Booked: Comminges, Rae.

Sheff Utd Kenny, Halford (Ward 41), Naysmith, Morgan, Kilgallon, Cotterill (Lupoli 84), Montgomery, O'Toole,Stephen Quinn, Naughton, Henderson (Beattie 70).

Subs Not Used: Howard, Bromby.

Booked: Halford, Naughton, Montgomery.

Goals: Cotterill 25 pen, Ward 46, Stephen Quinn 87.

Att: 17,942

Ref: Paul Taylor (Hertfordshire).