After securing the signature of Croatian stopper Ivo Grbic from Atlético Madrid only yesterday, the 28-year-old international was thrown straight into the starting line-up, tasked with stopping a Roberto De Zerbi side who have scored 17 goals in his six FA Cup games in charge.
However, possibly wounded by media comments suggesting Brighton have lost their tag as the league's entertainers after firing blanks the last two games, the Italian set out to put that right.
It was all too easy when the Blades’ back four dropped off to invite a long-range effort from Buonanotte, who unleashed a left-footed thunderbolt into the top corner, leaving Grbic with no chance.
The Seagulls weren't stopping there and made their dominance pay moments later, with Joao Pedro winning and converting a penalty after a subtle touch took him inside Jayden Bogle, who inadvertently clipped the Brazilian’s heels.
Yet, in a half totally dominated by the visitors, the Blades remarkably found themselves level with two goals on the stroke of HT.
First, William Osula’s fine work down the right resulted in a cross aimed at Ben Brereton Díaz, but before the ball could reach the Chile international, Bart Verbruggen threw out an arm to divert it kindly into the path of Gustavo Hamer, who smashed home from close range.
Osula then found himself on the end of a similar cross to the one he had provided moments earlier, making no mistake in heading past Verbruggen to send the home crowd into raptures despite an agonising VAR offside check.
It was Jayden Bogle’s cross that brought the Blades level, but ecstasy led to agony once more as he gave away the game's second penalty, this time for a blatant handball in stopping Ferguson from getting his head to the ball.
Pedro stepped up once more with the same outcome into the opposite corner, making it 10 perfect penalties in all competitions for the Brighton marksman.
High on confidence, Pedro still had time to round off his hat-trick with a long-distance effort of his own that arrowed into the bottom corner to finally put the game beyond doubt.
After reaching the quarter-final stage or better in three of the last four seasons, the Blades’ attention now turns to bridging the seven-point gap to Premier League safety with Danny Welbeck adding a fifth in stoppage time.
Meanwhile, the Seagulls remain unbeaten during this calendar year, and the chance of some much-awaited silverware looks a genuine possibility under De Zerbi’s stewardship.
Flashscore Player of the Match: Joao Pedro (Brighton & Hove Albion)
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