Wolves’ survival hopes and Gary O’Neil’s job security are intrinsically linked to the form of Matheus Cunha. The Brazilian created one and scored another here to secure a first league victory of the season and take the pressure off his manager for the time being at least.

Cunha’s quality was the difference between two underwhelming sides. Southampton’s problem is scoring goals and they brought a rubber spoon to a knife fight to hand Wolves a first Premier League clean sheet of the season as they doubled their points tally thanks Pablo Sarabia and Cunha.

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O’Neil knew the importance of the result, celebrating after the final whistle by fist-pumping in front of the fans but the reality is they have won twice in 21 league games. “The win was not about me; a lot was made about me and my future but I am really comfortable,” he said. “Today’s about Wolves and the players and the fans.”

If there was tension in the buildup with questions about O’Neil’s employment, it was alleviated inside two minutes when Wolves counterattacked after a dreadful Kyle Walker-Peters header. Cunha picked up the loose ball and drove forward before slipping the ball between defenders and Sarabia’s smart first touch took him round Aaron Ramsdale before finishing.

The winger was heavily criticised for his performance last weekend against Crystal Palace but was all forgotten and he enjoyed the adulation as he saluted the crowd.

Despite having more than 70% of possession, Southampton failed to produce a shot on target. They were punished for their chronic failings in the 51st minute when Cunha received a pass 30 yards from goal, got it out of his feet and whacked the ball powerfully beyond Ramsdale, who was booked for angrily claiming there was a foul in the buildup.

While the goalkeeper was complaining, O’Neil was embracing Cunha, knowing the short-term significance of his performance. “He’s a maverick,” O’Neil said of Cunha. “I don’t do much work with Matheus on his quality, just try and get him in the right places because he is tough.

“I have said we may lack quality in moments and we did today really, apart from Matheus. His two real moments of quality were massive for us because the rest of the group showed real fight, real togetherness and real spirit. But without that little bit of magic to unlock the door a couple of times, it would have been a tough afternoon.”

Considering Wolves had conceded 27 goals in their previous 10 matches, Southampton will be disappointed by their failures in the final third as they do not possess anyone at Cunha’s level. The visitors were repeatedly in dangerous positions and overwhelmed Wolves at times but O’Neil deserves credit for acknowledging the struggles in defence and moved from a back four to a five to stem the flow of attacks, adding some reinforcement when it was needed.

Southampton justifiably complained that Ryan Manning’s supposed equaliser was incorrectly ruled out after an intervention from the video assistant referee, but it would have hidden their inadequacies. It looked an innocuous coming together in the box when Mateus Fernandes ran into Nélson Semedo, but after reviewing the footage, the referee, Thomas Bramall, felt it was worthy of a foul and ruled the goal out.

“The decision is a tough one,” Russell Martin said. “He’s not tried to play the ball. Maybe it’s a penalty. Gaz [O’Neil] would, of course, disagree. The second goal is a foul [on Cameron Archer] for sure.

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“When you sit in Stockley Park, you have the benefit of pausing it and watching it at loads of angles. And his shirt’s nearly off his back from [Craig] Dawson but it is what it is.”

Even with a two-goal advantage, few in Molineux felt confident Wolves would see out the match unscathed. There was an eerie silence whenever Southampton attacked, but they lacked anything akin to creativity as their domination of possession was not matched by competence with the final ball. “The only thing I’m disappointed with today is we didn’t create more,” Martin said.

The two teams have a Premier League victory each now, at least, but it feels like they have a long ­season ahead of them.