A powerful display from Pompey Ladies proved too much for Cardiff at Westleigh Park.
Goals from Kirsty McGee and Lucy Quinn settled the FA Premier League southern division clash.
It was the perfect response to the defeat in London against West Ham in their previous outing.
Blues joint bosses Katie Poore and Perry Northeast switched their formation from a 4-3-3 to a 4-4-2.
Gemma Hillier and Charley Wilson were handed the striker roles, with Jess Frampton coming in for her first start on the right of midfield.
It was a move Poore felt worked well as Pompey held a strong grip on the contest throughout.
She said: ‘The girls were fantastic and totally dominated from start to finish.
‘It was a great performance.
‘The team worked really hard and outplayed Cardiff from the first whistle.
‘We made the change in formation because we wanted to go at Cardiff down the wings.
‘Jess made her first start and she has come on leaps and bounds.
‘Our fitness really showed. We beat them all over the park in the challenges.
‘We dictated the tempo and were aggressive all over the park.’
The Blues started well and Frampton superbly teed up Hillier who was denied by a block from a Cardiff defender.
The ball rebounded to Quinn but she was forced out to a tight angle and shot over the crossbar.
Pompey struck first on 26 minutes.
Frampton’s cross was won in the air by Wilson and midfielder McGee was in the right place to thunder the ball home from five yards out.
Cardiff attempted to respond but home keeper Sadie Blakely denied them with a strong hand to push a shot wide of the post.
She then punched the ball clear from the resulting corner.
Quinn almost doubled the lead just before half-time but her clever dinked shot was superbly saved.
It was a similar story in the second half as the home side commanded the play.
Quinn went close again when she forced another superb save from the Cardiff keeper after beating her marker.
Ellie Crabb made her Blues debut from the bench when she entered the fray on 70 minutes.
Then, five minutes later, Pompey clinched victory.
Hillier was fouled on the edge of the box and Quinn drilled a superb low free-kick into the net.
Poore and Northeast have now guided the team to two wins from two home matches this season.
The Blues sit second in the early table behind leaders Gillingham.