For a moment, Mohamed Salah’s shirt was gone with the wind, resting somewhere on the edge of the Southampton box. He had whipped it off, baring his lean, cartoonish torso in filthy conditions as he celebrated his second goal, from the penalty spot, to open up an eight-point lead at the summit of the Premier League, in front of the visiting Liverpool supporters going berserk in a pocket of this stadium. Then Luis Díaz retrieved Salah’s No 11.

On the face of it, at kick-off this was a mismatch between the teams top and bottom of the division but Liverpool, who opened the scoring through Dominik Szoboszlai, trailed to goals by Adam Armstrong and the impressive Mateus Fernandes. But Salah restored parity, struck the winner and then hit a post late on to leave Arne Slot’s side admiring the view. Slot’s businesslike thumbs up to the away end at the final whistle was the crowning moment, though they will have to improve when Real Madrid come to town on Wednesday.

Related: Arne Slot ‘not getting carried away’ despite Liverpool’s sparking start

There were plenty of positives for Russell Martin but ultimately this was another dispiriting defeat, an encouraging performance undone by individual errors. The Southampton manager has been wrestling to find a winning formula to avert an immediate return to the Championship and made five changes, handing the 6ft 7in striker Paul Onuachu his first league start in 18 months, since Saints were relegated last year, while Ryan Fraser was given the daunting task of shackling Salah from left wing-back. Alex McCarthy had a nervy game after replacing the injured Aaron Ramsdale in goal. The accusation levelled at Martin since he began life in the dugout at MK Dons in League One has been his teams’ tendency to overplay and the slapstick if not comical manner of Liverpool’s goal on the half-hour only served to add another log to the raging fire of debate.

Martin does not wish for Saints to self-sabotage. McCarthy rolled the ball to Fernandes and pointed upfield, seemingly not accounting for the traffic on the midfielder’s radar. Fernandes, hounded by Curtis Jones, passed the ball to Flynn Downes, standing on his goalline. He panicked in possession and hurried a half-baked clearance straight to Szoboszlai, who took a touch to compose himself before lining up a majestic finish. Martin shook his head and winced after Szoboszlai caressed an unerring left-foot shot in off a post. Downes almost immediately made amends, drawing a fine save from Caoimhín Kelleher.

“I ask them to play quickly so I take responsibility for that,” Martin said. “I think the players who were in the Premier League [with Southampton] last time feel very differently about this season. We have to eradicate those moments to give ourselves a chance.”

Onuachu had been a handful, earning olés from the home support, and Liverpool will have welcomed his premature exit with a hamstring problem after colliding with Cody Gakpo six minutes into the second half. The only problem for Liverpool was that Southampton still had Tyler Dibling on the pitch. The 18-year-old, who made his England Under-21 debut last week, has been Saints’ beacon of light during a draining few months. Dibling excelled on his Premier League debut against Manchester United in September, his direct running causing havoc and he won a penalty which Cameron Archer failed to convert.

Dibling won another spot-kick here, haring forward after seizing on a rare lapse by Virgil van Dijk and drawing a crunch from Andy Robertson. The referee, Samuel Barrott, pointed to the spot. This time, after the VAR, Michael Oliver, in a hoodie at Stockley Park, concluded the foul occurred on the edge of the 18-yard box – some angles appeared to show first contact happened just outside the area – Armstrong stepped up. His penalty was poor and allowed Kelleher, diving to his right, to repel his effort, but the striker sent the rebound through the goalkeeper’s legs to level.

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Dibling was at the forefront of every Saints attack and the catalyst for the superb counter that culminated in Kelleher fishing the ball out of his net 11 minutes after the interval. A move that inadvertently began with McCarthy fumbling a Liverpool corner ended with Fernandes neatly side-footing home Armstrong’s cross. Fraser had released Dibling, who on the touchline exquisitely checked back to eliminate Szoboszlai. Dibling then freed Armstrong, who lured Robertson, Ibrahima Konaté – who struggled all game – and Conor Bradley with him, then kept his cool to locate Fernandes, who calmly did the rest. The Portuguese has been another big plus.

However Southampton, enterprising going forward but vulnerable at the back, have a habit of leaking points. Liverpool’s equaliser was another sickener. Ryan Gravenberch sent a routine pass down the right channel, over the top of Kyle Walker-Peters, and McCarthy rushed from his goal to meet it. By the time it dawned on McCarthy that it may not have been the best move, it was too late as Salah cutely zipped the ball past him and into a gaping net.

McCarthy, to his credit, helped Southampton survive a few more hairy episodes but then the substitute Yuki Sugawara gifted the visitors another chance, handling Salah’s cross at the back post. The man himself buried his spot-kick.