Moussa Djenepo scored just 78 seconds after coming on as a second half sub to inspire Saints to their first win of the season at ten-man Brighton.

The £14m summer signing produced a moment of magic to score the opening goal of the game before Nathan Redmond added another in stoppage time at the Amex Stadium to get Saints’ Premier League campaign up and running.

It wasn’t always the most convincing performance given Brighton had to play an hour with ten men after the sending off of Florin Andone for a terrible challenge on Yan Valery.

But getting the result was much more important than how it came for Saints after back-to-back defeats in their opening two fixtures.

There was also a Premier League debut for Kevin Danso, who was given a baptism of fire playing in an unfamiliar left back role in a 4-2-2-2 formation after Ryan Bertrand suffered a late injury.

Angus Gunn was the first keeper called into action as he dived down to his right to save Neal Maupay’s slightly scuffed effort from just inside the area on five minutes.

Maupay threatened again three minutes later with a header from a dangerous inswinging Leandro Trossard corner but it deflected wide off Jan Bednarek who was in good order tight to the Brighton attacker.

Danny Ings, who scored his first goal of the season by closing down a clearance from the goalkeeper against Liverpool, nearly got another in the same way on 15 minutes.

He pressed Mat Ryan when the Brighton stopper had the ball at his feet and was struck by the attempted clearance but this time it went to safety.

Brighton went close again on 22 minutes as Trossard stood up a cutback cross from the left by-line that found the head of Martin Montoya, but he could only steer it wide from ten yards out.

The game swung in Saints’ favour on the half hour mark when Brighton were reduced to ten men.

It came out of nothing as Andone’s heavy touch saw him chasing the ball and Valery and, for no apparent reason, he stamped down on the Saints right back’s leg.

It was a needless and senseless challenge that referee Kevin Friend quite rightly punished with an immediate red card.

Brighton changed formations from a back five to a back four and Saints had a full hour to try and take advantage having been gifted the perfect chance to notch up a first win of the season.

Nathan Redmond tried to give his side the lead on 36 minutes with a driving run from deep and a drilled low shot that was well struck but too central to seriously threaten Ryan.

Brighton thought they had taken the lead two minutes later as Lewis Dunk headed home a Trossard corner but it went to VAR which proved that Dan Burn was clearly offside as he stood in front of Gunn and sent the keeper to the ground as he backed in.

Brighton didn’t start the second half like a team looking to just run down the clock and had the first shot of note three minutes after the restart as Solly March’s strike forced Gunn into a save.

Trossard was the next to have a go as Saints struggled to get to grips with Brighton’s fast start but his effort went wide.

Hasenhuttl acted quickly in bringing on Moussa Djenepo for Valery on 53 minutes. Djenepo took up an attacking position with Ward-Prowse dropping to right back.

It paid immediate dividends as Djenepo scored less two minutes after coming on.

Ings delivered a superb crossfield ball to the left that Djenepo brought down before pushing forward and opening up his body to curl a superb right footed shot into the far corner to give Saints a much needed lead.

Ings linked up well with Che Adams next but the striker’s shot was blocked by an excellent sliding challenge from Burn.

Saints were pressing forward in search of a goal to kill off Brighton’s challenge and Redmond went agonisingly close with a shot from 20 yards that only narrowly missed the target.

Brighton were not down and out and were creating far more than Saints would have liked given the situation. Davy Propper had space for a shot from outside the area for the Seagulls but curled it into the arms of Gunn.

The Saints keeper was helpless with four minutes remaining as a corner broke to Jurgen Locadia who slammed a half volley into the post.

With Brighton committing everybody forward Saints had the chance to seal it on the break in stoppage time but Stuart Armstrong was denied by Ryan.

However, they did wrap up the points as Sofiane Boufal tricked his way to down the left and squared the ball across goal to Redmond who slid in to turn home from a yard out at the far post.

There was still just about time for Brighton to clip the top of the crossbar but the win was already assured for Saints.