Substitute Carl Asaba destroyed Steve Coppell's hopes of a dream start to his career as Brighton manager with a second-half hat-trick as the Seagulls slumped to their 11th consecutive defeat.

Brighton were two up at half-time and looking anything but relegation fodder as they went in search of a first home victory of the season.

But they could not hold on as the high-flying Blades battled back.

United boss Neil Warnock had warned his players to expect their toughest test of the season so far in the wake of Coppell's appointment as boss.

Indeed, Brighton went ahead when Gary Hart, who was recalled to the starting line-up by Coppell, met Graham Barrett's cross with a powerful header past Paddy Kenny.

Eleven minutes later Barrett, on loan from Arsenal, scored his first goal for the Seagulls when he thumped a header into the roof of the net from Bobby Zamora's left-wing cross.

Warnock sent on Asaba in the 60th minute for his first appearance for a month after a back injury, and United pulled one back 10 minutes later when Michael Brown fired in a low shot from the edge of the box.

Asaba on fire

They were level after 77 minutes when Michael Tonge - under the watchful eye of a Tottenham representative - burst forward from midfield and drew a tackle, with Asaba pouncing on the loose ball.

The substitute striker was then bundled over in the penalty box by Brighton goalkeeper Michels Kuipers and got up to tuck away the 86th-minute penalty.

He completed his hat-trick with another penalty two minutes later after Adam Virgo had pulled down in-form striker Wayne Allison.

Brighton showed their teeth even before they scored, and Shaun Murphy did well to clear from a near-post corner from Paul Watson, before Barrett struck a long-range effort wide.

But Warnock's side did not take it lying down and three times called Kuipers into action, twice saving promising efforts from Allison and then tipping a Brown free-kick over the top.

But it was Brighton who made the breakthrough and once they were two up everything looked set for the perfect start for Coppell - until Asaba intervened.

Brighton: Kuipers, Watson, Virgo, Butters, Mayo, Hart, Carpenter, Oatway, Brooker, Zamora, Barrett. Subs: Rogers, Wilkinson, Packham, Marney, Hinshelwood.

Sheff Utd: Kenny, Yates, Murphy, Page, Ullathorne, Ndlovu, Tonge, McCall, Brown, Boulding, Allison. Subs: Kozluk, Asaba, Montgomery, de Vogt, McGovern.

Referee: P Prosser (Gloucestershire).