Pompey put their Carabao Cup defeat behind them as they easily beat Oxford United 4-1 at Fratton Park to maintain their 100% league record.
Kenny Jackett's men could have had the game wrapped up before half-time as they were dominant and create all the chances, with Karl Robinson's men struggling to get a foothold in the game.
A few half-chances were wasted before the tenacious Oli Hawkins won the ball high up the pitch from James Hanson and was then brought down in the box by the same player.
Gareth Evans stepped up to take the spot kick but his poor penalty was saved by Jonathan Mitchell and the rebound cleared before Jamal Lowe could get to it.
More chances followed as Naylor's air-shot from point blank range, Evans' blocked shot and Hawkins' failure to get on the end of a teasing cross meant the scoreline stayed goalless at the break. All Oxford had to show for their first half efforts were a collection of bookings, including one for Shaun Derry on the Oxford bench.
Anton Walkes is another who deserves credit after some recent poor showings. He won most of his tackles and supported the attack well when he could, just like any quality full back should do.
It should be stated, that as impressive as Pompey were yesterday, Oxford were dreadful and didn't start playing until the game was over. The season may only be three games old but they look like a team who are in for a struggle.
Next up is a Tuesday night trip to Bristol Rovers and that will be a much more difficult game and Pompey's biggest test of the season given how in the past they've always crumbled away from home during midweek matches against any decent opposition.
The same fixture was arguably the breaking of Pompey last season but this season it could well be the making if they can make it four league wins out of four.
Thankfully, Pompey's relentless pressure continued into the second half continued and some good work from Lowe allowed him to centre the ball for Hawkins and although he couldn't score, he passed the ball to Evans who did after making space for himself to shoot.
The impressive Lowe played a part in the second goal soon after as his cross was glanced into the net by Rob Dickie for the first of the two own goals in the match.
Oxford's heads dropped after that and the third goal soon arrived when Evans' corner was helped on by Clarke and Hawkins before Lowe stabbed the ball home from close range and end the game as a contest.
The only disappointing point to come from this performance was how Pompey took their foot off the pedal with ten minutes to go as the post came to the aid of the hosts to prevent Oxford pulling a goal back with the Pompey defence ripped apart too easily on the break in both instances.
Karl Robinson's men did get on the scoresheet as Jack Whatmough somehow skewed Tony McMahon's cross past Craig MacGillivray on the day before his 22nd birthday. Incidentally, that was the U's first goal in the league this season.
Rather than panic and suffer a late siege from the visitors, Lowe capped his performance with what will certainly be a goal of the season contender, running the ball down the pitch before beating a defender and curling the ball beyond Mitchell from the edge of the box.
The final whistle blew to confirm a resounding victory for the Blues and much of that was down to new arrival Ben Thompson whose performance won plaudits from those watching.
Some fans criticised Jackett for bringing in another "defensive midfielder" on Friday yet the Millwall loanee showed he can do more than just get stuck in as he showed an excellent range of passing and he never gave up chasing lost causes. On this evidence, he could be a hell of a signing for Pompey.
Tom Naylor also markedly improved from his previous performances and his desire to get to the loose ball the second time Oxford hit the post to prevent them from scoring underlined his commitment.
Whilst Oli Hawkins may not have scored he still had a major role to play in the first and third goals and he gave the Oxford defenders a hard time up front. If he could be more accurate with his attempts at goal, he could be a massive asset this season and Pitman will struggle to reclaim his place in the team.
Anton Walkes also deserves some credit after a string of poor performances recently as he was excellent yesterday. He won the majority of his battles and supported the attack well, just like any quality full back should do.
It should be stated, that as great as Pompey's showing was and every player looked good, Oxford were dire and even though the season is only three games old, they look bereft of quality and could struggle all season.
As for Portsmouth, a much tougher test awaits on Tuesday night when they travel to the Memorial Ground to take on Bristol Rovers.
Pompey Player Ratings
Craig MacGillivray: 7 - Little to do until late on when he made a couple of decent saves.
Anton Walkes: 7 - Best performance of the season.
Matt Clarke: 7 - Typical quality performance.
Jack Whatmough: 7 - Own goal aside, looks very accomplished for someone who is still in the youth of his career.
Lee Brown: 7 - Solid and supported the attack well.
Tom Naylor: 7 - Looked good in a midfield trio.
Ben Thompson: 9 - Extremely impressive debut. Ran the show.
Gareth Evans: 7 - Squandered spot kick but got his goal eventually and always worked hard.
Jamal Lowe: 9 - A constant menace, especially in the second half.
Ronan Curtis: 6 - Quieter than previous games.
Oli Hawkins: 7 - Assisted two goals but needs to add scoring regularly to his game.
Pompey Player Ratings
Luke McGee
Christian Burgess
Brandan Haunstrup
Ben Close
David Wheeler (Curtis 80): N/A - Not given enough time to make an impact.
Conor Chaplin
Brett Pitman