Adam Lallana struck against his former club as Brighton inflicted more misery on struggling Southampton with a resounding 3-1 Premier League victory at St Mary’s. The Saints academy graduate Lallana benefited from a major blunder from the home goalkeeper Gavin Bazunu to put Albion ahead before Romain Perraud’s calamitous own goal doubled their half-time advantage. Brighton winger Solly March thumped home a third to cap a dismal first home game in top-flight management for the Southampton manager, Nathan Jones. James Ward-Prowse pulled a goal back by heading in on the rebound after his 73rd-minute penalty was saved by Robert Sánchez but a Southampton fightback never looked likely. Defeat for the error-strewn hosts means they remain languishing in the relegation zone and leaves Jones in no doubt about the magnitude of the job facing him. “We never really gave ourselves a chance of winning,” said Jones. “We didn’t do the basics well enough and didn’t deserve anything from the game. We gifted them two goals. We have to make sure we have a foothold in the game and at the minute we’re not giving ourselves a chance.” The former Luton manager Jones was forced to wait almost seven weeks for his first taste of top-flight action on home soil, having replaced the sacked Ralph Hasenhüttl just two days before a 3-1 defeat at Liverpool on 12 November. Things quickly turned sour for the Welshman on an afternoon when his listless team were jeered off at the end of each half. Brighton, still without the World Cup winner Alexis Mac Allister, began brighter and edged ahead in the 14th minute as Lallana’s glancing header embarrassed the Republic of Ireland international Bazunu. The Brighton midfielder turned neatly deep inside Saints’ territory and then played the ball wide to March before darting into the box to direct the subsequent inswinging cross through the arms of the blundering keeper. The former England international Lallana, who left Saints for Liverpool in 2014 having joined the club’s academy aged 12, was booed in the early stages but his celebration was subdued. Southampton resumed action after the World Cup with the worst home record in the division and the avoidable opener swiftly prompted grumblings of discontent in the stands. The captain, Ward-Prowse, flashed a free-kick narrowly wide to offer some encouragement before the hosts fell further behind in catastrophic fashion, darkening the mood. Saints’ defence had struggled to contain Pervis Estupiñán and Kaoru Mitoma on Brighton’s left from the first whistle and 10 minutes before the break they combined for the former to deliver a tantalising low cross, which Perraud clumsily directed into his own goal under pressure from March. Southampton began the second period with greater purpose and Samuel Edozie twice threatened. But March soon halted any growing momentum by cutting in from the right to smash a stunning drive into the top left corner from around 25 yards. As Southampton supporters watched on with gloomy expressions, Brighton’s capacity following revelled in their side’s scintillating display, with chants of “the south coast is ours” followed by ones about the possibility of a European adventure next season. Saints finally gave themselves some hope when the lively Edozie was felled in the box by Pascal Gross. Sánchez, who was booked for the delaying of the spot-kick, saved Ward-Prowse’s initial kick after diving to his right but was powerless to repel the follow-up effort. The Spain international later risked a second yellow card after a clash with Che Adams before Brighton coasted to a third league win from four games to finish the day still in seventh, denied a rise of one place when Liverpool won the 5.30pm game at Aston Villa. “For the quality of play, the strategy of game, it was a fantastic day,” said the Brighton manager, Robert De Zerbi. “For me, the most important is not the result, it’s how much my players follow me. I’m very happy. We played probably the best game with me as a coach. We are improving.”