Goal machine Watson at the double as brilliant Cobblers paste Pompey

Everything felt so doom and gloom after losing at Swindon only seven days ago but suddenly Town have momentum and confidence very much on their side following back-to-back wins for the first time this season - and both coming against top-10 sides at that.

The first-half was remarkable as it was thrilling for Cobblers supporters as their side, having only recently ended a five-game drought at home, stormed into a four-goal lead against a team sitting fifth in the division.

That man Watson scored the first two, a magnificent free-kick and a towering header, to continue his sensational form before Fraser Horsfall and then Sam Hoskins left Portsmouth shell-shocked.

The second-half saw the visitors applying plenty of pressure without much penetration and even a late consolation could not take the gloss of a famous and impressive victory.

Town, who only ended an 11-game winless run on Tuesday, are now up to 19th and have given themselves a real chance of maintaining their League One status.

Jon Brady picked the same team that beat Plymouth in midweek while former Town man John Marquis returned to lead the line for Pompey.

There was nothing in the game in a scrappy and cagey first 20 minutes but things soon burst into life in rather dramatic fashion and it was that man Watson that kicked it all off.

Mickel Miller was brought down 25 yards from goal and Watson took over set-piece duties, curling a wonderful free-kick up and over the wall and into the top corner, with Craig MacGillivray grasping at thin air.

That made it five in five for the midfielder but it was to get even better just two minutes later.

Nice play down the right between Sam Hoskins and Peter Kioso led to a corner from which MIller's delivery was headed in by - yes - Watson for his sixth goal in the past five games.

Cobblers went for the throat and Hoskins nearly added another as MacGillivray palmed away his shot after some wonderful skill, but from the subsequent corner Town did indeed score a third.

Again Miller's delivery caused chaos in the Pompey penalty box and Horsfall forced the ball home from close-range with the linesman signalling it had crossed the line before being hacked clear.

Ronan Curtis took Portsmouth's first shot which Jonathan Mitchell easily saved, but Town continued to threaten with Watson just unable to pick out an unmarked Ryan Edmondson, who then saw an effort tipped over the crossbar.

Astonishingly, Cobblers increased their lead yet further two minutes before half-time.

For the third time in the half, MacGillivray came racing out of to head clear but only found Hoskins who showed superb composure to take get the ball under control and lift a majestic chip over Pompey's stranded goalkeeper and into the net.

That meant the home side took a four-goal lead into half-time after an extraordinary opening 45 minutes.

Pompey had no choice but to come out all guns blazing in the second-half, however again they were in a mess at the back with Peter Kioso's close-range effort having to be held by MacGillivray.

Kenny Jackett made four subs on the hour-mark and one of those almost pulled one back immediately, Jordy Hiwula drilling just wide of the far post.

Two other substitutes did have a hand in a goal 17 minutes from time though when Harvey White was fouled by Horsfall in the penalty box and Ellis Harrison just about powered his spot-kick through Mitchell.

But despite applying more pressure on the home goal, Pompey never threatened Mitchell between the posts and it was opposite number MacGillivray who had to be called upon in stoppage-time, denying Edmondson to prevent an even heavier beating.

Match facts

Cobblers: Mitchell, Kioso, Horsfall, L Jones, Mills (c) (Harriman 68), McWilliams (Rose 75), Sowerby, Watson, Hoskins, Miller, Edmondson

Subs not used: Arnold, Korboa, Marshall, A Jones, Chukwuemeka

Portsmouth: MacGillivray, Brown, Naylor (c), Whatmough, Cannon, Nicolaisen (White 59), Byers (Bolton 59), Raggett, Harness, Curtis (Hiwula 59), Marquis (Harrison 58)

Subs not used: Ward, Williams, Daniels

Referee: Andy Haines