Southampton extended their unbeaten run to 17 games as they overcame a dogged Plymouth side 2-1 at St Mary’s.

Taylor Harwood-Bellis glanced a header off the Argyle post as the hosts dominated the first half but failed to breach the visitors’ defence.

The game turned in a 35-second period 10 minutes after the break as Plymouth’s Bali Mumba wrongly had a headed goal disallowed for offside. Saints went straight up the other end and Carlos Alcaraz brilliantly curled a 20-yard effort into the top corner.

Che Adams finished well to double the lead soon after before Ryan Hardie’s stoppage-time goal set up a nervous finish.

The win – which moves Saints to within two games of equalling the club record of 19 consecutive matches unbeaten – ensures they will go into 2024 in third place in the Championship, while the Pilgrims remain seven points above the drop zone.

It was a first defeat in three games for Argyle’s director of football Neil Dewsnip, who has been in temporary charge since Steven Schumacher left his role as manager to become Stoke City head coach 10 days ago.

Saints started strongly as Adams had a fifth-minute goal disallowed for offside while Adam Armstrong’s bid to lob Conor Hazard from five yards inside the Argyle half went just over the bar as the Plymouth keeper scrambled back.

Alcaraz blasted a long-range effort just wide of the Argyle far post soon after as dominant Saints had 81% possession in the first 10 minutes before Harwood-Bellis hit the upright six minutes later from a corner.

Argyle began to frustrate their hosts as the half wore on, their disciplined defensive line catching Saints offside a number of times, but they had little to offer as striker Ben Waine cut an isolated figure.

The visitors finally got into the home penalty area after 41 minutes when Morgan Whittaker was found on the break, but Samuel Edozie did well to block his effort before Kyle Walker-Peters and Ryan Manning had shots saved by Hazard as the half drew to a close.

Alcaraz brought an excellent save out of Hazard six minutes after the break as he burst into the box and saw his goal-bound effort deflect off Lewis Gibson.

But the Argentine did not have to wait long to superbly put his side ahead, but not before Mumba’s goal was wrongly adjudged offside as he headed in unmarked from Whittaker’s cross at the back post, with replays showing Jan Bednarek had kept him onside.

There was no doubt about Saints’ second goal as Harwood-Bellis chipped a ball over the defence and Adams timed his run perfectly, held off Gibson and finished well.

It could have been more for the hosts as substitute Joe Aribo curled a 20-yard effort just wide of the top corner, Armstrong had a shot well saved by Hazard and Sekou Mara had a close-range effort blocked by Dan Scarr.

Hardie replied for Argyle late on when Gavin Bazunu – who had had little to do in the Saints goal all night – badly controlled a backpass and the Scottish forward deflected the ball in from close range.

It could have been 3-1 moments later when Ryan Fraser was put through on goal, but Hazard saved well with his leg.

Southampton manager Russell Martin:

“I think the performance was brilliant. We should score a couple more goals I think, but we showed patience, aggression with the ball, created a lot, had 26 shots at home.

“So apart from the last six minutes I’m so happy with the performance. But I don’t want that period to affect how I feel about what the players did for the rest of the game because some of it was really brilliant.

“We should have a clean sheet. I am annoyed and the players are, it was really flat in there, but I said to them ‘you’ve just won another game’.”

Plymouth director of football Neil Dewsnip:

“I think anybody who’s watching at home will have seen it on TV, we saw the re-runs very, very quickly and it’s really tough to take.

“Not just the fact that we’ve missed out on the goal, but the game restarts with three of our players who are celebrating the wrong side of the ball and our gameplan was to defend deep and counter-attack and it’s difficult to do that with three players less.

“It was competitive and structured and well thought out I thought, but the first goal kills us really. But I’ve got to say congratulations to Southampton, I thought they played exceedingly well. They’re a real threat, particularly at home.”