Northampton would have come to Fratton Park looking to frustrate the League One leaders and keep them quiet.
But instead the visitors found themselves two goals down inside the opening 16 minutes to a rampant Pompey side.
Connor Ogilvie’s headed opener was added to by a Paddy Lane brace and Callum Lang’s volley on his full debut to seal a 4-1 victory.
That was despite Tom McIntyre’s controversial sending off early in the second half and Marlon Pack was delighted with such a strong opening.
Pompey’s skipper said: “The way we began the game gave us a really good platform – that’s how we always want to start.
“It’s easier said than done when teams come to Fratton Park, but we want a high tempo with our fans behind us.
"We want to be able to kill teams off when we’re dominant, so it’s good to give the fans a lot to cheer about."
“That’s something we’ve spoken about a lot and it’s good to showcase that and to reap the rewards from it.
“We want to be able to kill teams off when we’re dominant, so it’s good to give the fans a lot to cheer about.
“The character shown by the boys to go down to 10 men, continue to press score two more goals is testament to what we’ve built this season.
“It was a strong tackle by Tom, but if he doesn’t do that and goes in with a limp leg then I think he gets injured himself. It didn’t look high or reckless.”
Two of Pompey’s goals against the Cobblers came from free-kicks that were swung into the box by Pack.
He said: “We’ve had a few set-piece takers this season and I’m one of them – they’re mine to lose at the moment!
“You’re just looking to hit an area and we’ve shown that we can be very productive with big lads who can attack the ball.”