The unpredictability of Roberto De Zerbi’s Brighton is among their most endearing characteristics. Yes, they are very capable of horrid days, where querying their entire approach to football comes easily. But then they deliver the sort of 90 minutes of mesmerising, efficient beauty that returns viewers to a state of fawning. Brighton’s Sunday in Sheffield was, in part, laid on by the most amenable of hosts. But then, so the cliche goes, facing 10 men for much of the game can be among the most difficult of challenges. Yet what unfolded at Bramall Lane was akin to a training ground exercise: Premier League wins rarely come more easily. When Facundo Buonanotte and Danny Welbeck grabbed a pair of quickfire first-half goals, victory was all but assured. Much later, Jack Robinson’s own goal and a rapid Simon Adingra double simply added additional gloss. “We want six,” the delighted tra­vellers yelled. “We want one,” came the lone cry of one particularly exasperated ­Sheffield United fan in response. Pascal Gross spent his afternoon pinging deliveries with unnerving accuracy, Kaoru Mitoma danced away deliciously on the left, while Adingra did likewise over on the other side. Everything else in between? Death by a thousand passes. Most frustrating for Chris Wilder will be that Brighton have hardly sparkled on their travels recently. They arrived without a win in half a dozen top-flight away games, ­including an embarrassing slip‑up at Luton. United, ­having emerged ­victorious from Kenilworth Road last weekend, had some hope to which they could grasp. Then, with the game in its infancy, that hope evaporated when Mason Holgate was dismissed after a hefty challenge on Mitoma. For all the abuse the crowd aimed in Stuart Atwell’s direction as the game passed, the ­referee’s only real mistake was reaching initially for something ­yellow in response to ­Holgate’s offence. ­Fortunately the VAR, Michael Oliver, swiftly had Atwell monitor-bound, and an upgraded card appeared. Mitoma was able to continue. De Zerbi played it politically, stating he had not yet seen a replay. ­Wilder’s view was mixed: “I’m torn,” he said. “I’m a competitor. It was a very, very strong challenge and the game has moved on. Some people won’t want the game to move on and will expect physical contact, excessive force or whatever you call it. Winning the ball and challenging in that way is deemed not acceptable.” After Holgate’s dismissal, Brighton acted quickly and decisively to kill the contest. First, from Gross’s ­corner, Lewis Dunk nodded back across goal and Buonanotte steered the ball over the line. Just. For his next cross, Gross plucked a pitching wedge from his bag and delivered a deliciously inviting ball for Mitoma. Wes Foderingham’s palm away was strong, but Welbeck’s follow-up ­volley was stronger still. Brighton then settled into a ­hypnotic passing rhythm. United understandably recoiled hoping, as Wilder put it, “to stay in the game until the last 10 minutes”. To an extent that approach almost worked, although Brighton’s control was obvious. But then, with United poised to introduce an attacker or three, Brighton’s third came when Robinson’s attempt to cut out Mitoma’s cross went badly awry. Three quickly brought four and five. For his first, Adingra – back from a victorious trip to the Africa Cup of Nations – met a cross from Gross to finish superbly. Soon after, he beat Foderingham via a heavy ­Auston Trusty deflection. “We played a smart game, we understood the game,” a delighted De Zerbi said. “That for me is more important than the number of goals. The players understood the difficulty of the game of 11 v 10.” It was, for the umpteenth time this season, a chastening afternoon for United. Holgate’s ­departure meant that, just 30 minutes in, Wilder and Alan Knill concluded the way ­forward was to remove William Osula, their one starting attacker, and introduce Trusty as a defensive reinforcement. Understandable, yes, but also a ­measure of just how grim times are. Ben Osborn at least had home fans dreaming of a comeback when he bundled in from a corner just before the ­interval. Alas, their joy was momentary. Atwell seemed, initially, to blow for a foul but, after another consultation with the pitchside monitor, the goal was ruled out for offside. At least, at that point, United had showed some fight. Not all of it was well directed; Vini Souza, in particular, seemed determined to kick all that came before him. But it was something, a little spark among the damp. By the close, those home fans who endured stoppage time in its entirety could barely muster the energy to jeer. They are all too aware that United have months of going through the motions ahead of them. Brighton’s prospects, though, are much more cheery. Soon, attention will turn again to the pursuit of silverware and to European travels.