Southampton won their sixth cup tie of the season to see off Blackpool at St Mary’s and progress to the last 16 of the Emirates FA Cup thanks to a brace from an unlikely source.

Romain Perraud had only scored three times in 45 Saints appearances ahead of this fourth-round tie, but the Frenchman was deadly in front of goal in firing the hosts into a 2-0 lead.

His first was a vicious free-kick that he took in the absence of the rested James Ward-Prowse, while his second came courtesy of a one-two in the box with compatriot Sékou Mara.

Saints had been comfortable up to that point, barring two important saves from 41-year-old Willy Caballero at the end of sporadic Blackpool counter-attacks, but the two-goal cushion was short-lived.

Midway through the second half, just five minutes after Perraud’s second, Charlie Patino pulled one back for the visitors, who pushed for a late equaliser but were unable to force a replay on the Fylde coast.

Nathan Jones rang the changes with eight alterations in all, including a first appearance of the season for Caballero in goal, who captained the side with Ward-Prowse given a rare day off.

The only survivors from the midweek Carabao Cup semi-final first leg were Lyanco, Mislav Oršić and Mara, as Jones selected an attacking line-up with Mohamed Elyounoussi and Joe Aribo flanking Roméo Lavia in midfield, and Oršić and Samuel Edozie supporting Mara from the wings.

First to go close was Oršić, still building his sharpness after his World Cup heroics, as the Croatian swept a first-time shot goalwards from 20 yards that was always curling away from Chris Maxwell’s right-hand post.

Mara’s enthusiasm to close down the Blackpool keeper landed him in hot water when he threw himself in the way of Maxwell’s clearance and inadvertently caught the Welshman – an offence punished by a yellow card. Contrary to the travelling fans’ desperate pleas, the VAR was not interested in upgrading to a red.

It was Saints making the early inroads, with the bulk of the threat coming from wide. Edozie had the beating of Blackpool’s left side, picking out Oršić from one cross, as his opposite winger showed impressive vision to spot the galloping Perraud to his left, but the sting was taken out of the Frenchman’s shot.

The same could not be said of Perraud’s next effort, as the left-back fired in his third goal of the season.

When Saints were awarded a free-kick two yards outside the penalty area, right of centre, St Mary’s wondered what might be coming next without Ward-Prowse on the field.

With Oršić and Perraud standing over it, the angle favoured the left-footer and the Frenchman did not disappoint, blasting the dead ball low to Maxwell’s right, as the keeper was beaten on his side of the wall by the sheer pace of the strike.

Blackpool were yet to threaten, but did respond to falling behind by mounting their best attack of the half.

Ian Poveda was set free through the middle. As Lyanco came across to hold him up, Poveda found Yates in space to his right, who had time to set himself and was only denied by a flying save from Caballero, who spectacularly helped the ball on its way over the bar.

The veteran shot-stopper was tested again by Andy Lyons’s low drive, before Edozie’s twinkle toes set up Elyounoussi for a fierce shot that was crucially blocked in front of Maxwell.

This was a first start in five games for Perraud but the goalscorer was enjoying himself, as a confident backheel freed Elyounoussi in the box as Saints resumed control of the first half.

When Elyounoussi returned the favour with a clever pass into the left-back’s path, Perraud’s cross deserved a better first touch from Edozie, who just allowed the ball to escape him.

Blackpool, second bottom of the Championship, responded well to Mick McCarthy’s first half-time team talk, as the new boss saw an instant improvement at the start of the second period.

Lyanco needed to get an important touch on a dangerous free-kick to help it on its way wide, before Caballero saved Saints once more.

The defending was nowhere to be seen when an innocuous ball down the left touchline somehow stayed in play, inviting Yates to run across and keep it in play before finding Poveda in acres of space bearing down on goal.

As Caballero advanced, the Leeds loanee tried to scoop the ball over his head but the keeper read his intentions, swatting it away with a big right hand.

The ball came straight back to Poveda, who still had all the time in the world to pick his spot, but tried to be too precise and clipped the outside of the post with his follow-up as Saints breathed a sigh of relief.

It was a major reprieve and one the hosts took full advantage of, as Perraud showed his class to double his tally and take the tie away from the Seasiders – or so it seemed.

Picking up possession outside the penalty area, Perraud found Mara in the box and followed his pass, taking his compatriot’s lay-off neatly in his path before drilling another unstoppable low shot past Maxwell.

The Saints supporters spent the rest of the game encouraging Perraud to shoot every time he received the ball, with a hat-trick in his sights, but it was Aribo going close with a deflected strike that had Maxwell scrambling across his goal and relieved to see the ball drop wide.

Just as Jones’s side thought they were home and dry, Blackpool reminded them they were still in a game.

Josh Bowler picked up possession inside his own half and left two Saints in his wake before finding Yates to his right, whose square pass across the box was intended for Poveda but instead fell kindly for Patino to steer in a goal back.

Substitute Theo Walcott, on for Oršić at 2-0, threatened to kill off the visitors once and for all, but watched his shot take a looping deflection and land on the top of Maxwell’s net with the keeper beaten.

This was not a comfortable finale for Saints, who had to withstand six minutes of stoppage time and three corners from which Maxwell stayed forward, but Caballero could catch and fall on the ball to ensure his teammates' hectic schedule would be spared another date in the diary.