Report: Downes the hero in dramatic late win

The seven added minutes had already been played when Saints forced a corner, which was delivered by Ryan Manning, knocked down by Taylor Harwood-Bellis and stabbed in by Downes from close range, sparking wild celebrations in front of the Northam Stand.

The hosts had stormed out of the blocks to take a two-goal lead inside 20 minutes, as Will Smallbone headed home in the first 60 seconds of the game, before Ché Adams continued his good recent form with another poacher’s effort.

But Watford got a foothold in the contest when Ryan Porteous saw his shot deflect in off Jack Stephens, leading to a nervy second half.

St Mary’s erupted when substitute Ryan Fraser had the ball in the net from Adam Armstrong’s pass late on, but the offside flag halted Saints’ celebrations before Watford replacement Ismaël Koné slotted in a crushing leveller five minutes from time.

But Saints still were not finished, as Armstrong saw a volley tipped over and Stephens forced the corner from which Downes won the game in the most dramatic fashion.

Russell Martin named an unchanged side following Tuesday’s 2-1 home win over Coventry, which, combined with defeats for Leicester and Leeds before Saints kicked off, added to the air of anticipation inside St Mary’s.

There was a noticeable buzz about an expectant home crowd that was ramped up another few notches by Smallbone’s instant opener.

With Saints attacking towards the Chapel Stand in the first half, Martin’s men made a flying start, working the ball wide to Adam Armstrong on the left, who was afforded enough time to come inside and cross with his right foot for the arriving Smallbone, who calmly headed the ball back across the rooted Daniel Bachmann in the Watford goal.

Will Smallbone celebrates his early opener

Saints soon assumed full control against a visiting team unbeaten in five games under interim head coach Tom Cleverley, who had overseen draws with promotion chasers Leeds, West Brom and Ipswich in that time.

The Hornets did have a sight of goal when Giorgi Chakvetadze lined up a shot from 20 yards, but his strike was tame and easily gathered by Gavin Bazunu.

Saints nearly punished them a matter of seconds later. Smallbone, fired up by his first goal since January, slid in to win the ball from Tom Dele-Bashiru, drove into the box and fired high and wide of the near post.

The first bit was brilliant, the second uncharacteristically uncomposed from the usually assured midfielder, who perhaps had better options to his left in David Brooks and Adams.

Ironically, it was those two players who combined for Saints’ second goal in the 20th minute.

It was not one Cleverley will care to see again, as Dele-Bashiru made a hash of clearing a low cross from Walker-Peters, again playing as Saints’ left-back, and Brooks was sharp to the mistake, capitalising with a quick cutback from the byline for Adams to tap home.

The striker will argue that was his fourth goal in four games, but the record books still have Saints’ first against Coventry down as a Walker-Peters strike, despite the ball clearly deflecting in off the No 10.

Ché Adams was in the right place at the right time to double Saints' lead

The next demonstration of Saints’ growing confidence came from the dancing feet of Joe Aribo, who threatened to tiptoe his way through the entire Watford defence, before the visitors responded with their best spell of the half.

Lively winger Yaser Asprilla tried his luck with a couple of runs at Walker-Peters, jinking inside and clipping the defender’s legs with a low shot that bobbled narrowly wide, before beating him on the outside and fizzing one across Bazunu’s goal that might have been tipped wide by the keeper, though a goal kick was awarded.

The travelling fans sensed something, and were soon bursting with belief when Porteous’s 20-yard strike nicked off the head of Stephens, leaving Bazunu wrong-footed and Saints under pressure for the first time in the game.

Emmanuel Dennis might have done better with a weak header from a set-piece as Watford pushed to level the scores, before Armstrong fired over on the stroke of half time after a brilliant first touch to bring the ball out of the sky.

Saints shot off target from the edge of the box again at the start of the second period, this time when Armstrong teed up Brooks, but Martin will have been pleased to see his side back in the ascendancy.

But in Porteous Watford had a secret goal threat of their own. The defender had only four goals to his name in his 54 previous appearances for the club, but had two more chances in quick succession to add to his first-half strike.

Towering above Walker-Peters at the far post, he was unable to direct a Chakvetadze cross on target, before applying a much more accurate touch to Jamal Lewis’s delivery, only for Harwood-Bellis to get himself back on the line and clear the danger.

Martin freshened up his midfield 11 minutes into the second half, replacing Aribo and Brooks with Stuart Armstrong and Fraser, before Cleverley made a triple change of his own.

Flynn Downes scores Saints' last-gasp winner

This was turning into an anxious afternoon for Saints by the time Chakvetadze volleyed wide from ten yards with a quarter of the game to go.

Saints’ willingness to score a third and put the result to bed was captured by Fraser’s desperate lunge to dispossess keeper Bachmann, leading to a booking for the Scot as Adams lifted the ball into the unguarded net to no avail.

With ten minutes left, Martin turned to Jan Bednarek immediately after Cleverley introduced 6ft 4in top scorer Mileta Rajović, before an offside flag denied the hosts the third goal they craved when Fraser calmly dispatched Adam Armstrong’s pass from a slick counter-attack.

There could only have been a matter of inches in it, but they would prove costly inches, as Koné found the goal St Mary’s had been fearing.

When the bounce of the ball deceived Downes in midfield, the half-time substitute took it in his stride and advanced towards the box, steering a precise low shot across Bazunu’s dive, almost in slow motion, to find the far corner.

Spurred into life, Saints poured forward in search of a winner, as Bachmann tipped Adam Armstrong’s volley over the top before Manning delivered the latest of late corners from which Downes forced the ball home, just in the nick of time.

Southampton: Bazunu, Bree (Manning 71), Harwood-Bellis, Stephens (c), Walker-Peters, Downes, Smallbone (Bednarek 80), Aribo (S Armstrong 56), Brooks (Fraser 56), Adams (Mara 80), A Armstrong.

Unused substitutes: Lumley, Rothwell, Edozie, Kamaldeen.

Goals: Smallbone (1’), Adams (20’), Downes (90+9’).

Yellow cards: Fraser.

Watford: Bachmann, Porteous, Pollock (Andrews 62), Hoedt (c), Chakvetadze, Kayembe, Dele-Bashiru (Koné 46), Lewis (Morris 61), Bayo (Rajović 78), Asprilla, Dennis (Martins 61).

Unused substitutes: Hamer, Sierralta, Livermore, Ince.

Goals: Porteous (34’), Koné (85’).

Yellow cards: Hoedt, Porteous.

Referee: Josh Smith.

Attendance: 30,347.