Abu Kamara provided a hat-trick of assists to help Pompey secure another comfortable League One home win.
The were more than 20,000 inside Fratton Park to witness it – the highest crowd for a league game since Arsenal came to town in a top-flight contest at the end of 2009.
It was the Royals who made the brighter start, but Paddy Lane opened the scoring towards the end of the first half and it was smooth sailing from there.
Marlon Pack fired the hosts further in front shortly after the interval before Callum Lang made sure of the points.
There was still time for Colby Bishop to tuck away his 16th goal of the season, while Charlie Savage grabbed a late consolation for the visitors.
John Mousinho made three changes from the side that beat Cambridge on home soil earlier in the week.
January signing Owen Moxon was handed a full debut in place of the injured Tom Lowery in the middle of the pitch.
Bishop and Lang also returned to the starting line-up, with Kusini Yengi dropping to the bench and Myles Peart-Harris missing out with a knock.
It was the visitors looking more like the table toppers in the opening stages and they caused Pompey plenty of problems.
Femi Azeez was first to go close, being afforded space to drive forward and hit a low shot that Will Norris got down to save.
The keeper also dealt with Paul Mukairu’s tame follow-up before dealing with a curling attempt from Lewis Wing.
But the hosts soon had a chance of their own, as Andy Yiadom could only clear Sean Raggett’s long pass straight to Bishop, whose shot was saved low down by David Button.
It was still the Royals looking more likely to break the deadlock, though, and Mukairu should have done better than flick Kelvin Ehibhatiomhan’s delivery over the bar from just a few yards out.
Wing then played a clever threaded pass through to Ehibhatiomhan, with Norris quickly off his line to deal with the danger.
Meanwhile, the Blues were left furious when referee Josh Smith allowed Reading to attack while one of their players was down injured, only to blow as soon as a counter-attack was launched.
They slowly started to settle into the contest as the first half progressed and began to look dangerous themselves.
Fratton Park had been noisy throughout, but it really came alive when the hosts opened the scoring on 36 minutes.
Kamara got past Michael Craig in the middle of the pitch and surged forward before laying the ball off for LANE.
He took a touch before drilling in a low shot that beat Button at his near post, with the keeper only able to help the ball into the net.
It might have got even better just before the break when Lane intercepted a wayward Mukairu pass and fired a shot narrowly past the post.
Half Time: Pompey 1 Reading 0
Pompey were looking to give their advantage a cushion – and it arrived within four minutes of the restart.
Kamara was the architect again, surging down the right and finding PACK, who dropped a shoulder to beat Amadou Mbengue and fired the ball home.
Reading brought on Sam Smith in an attempt to fight their way back and he immediately hit a long-range strike that was gathered by Norris.
But it soon got even better for the Blues after Moxon had done well to steal possession and find Kamara.
He played the ball across to LANG, who moved it onto his right foot before hitting a precise finish into the bottom corner.
Joe Rafferty then did well to pick out the same player inside the box, but the header from Lang lacked enough power to trouble Button.
And when Pack swung a teasing free-kick into the mixer, Conor Shaughnessy could only glance the ball wide.
Reading almost hit back at the other end, as Wing’s 20-yard free-kick cannoned down off the underside of the bar and was grabbed by Norris.
Mousinho introduced some fresh legs on 73 minutes, with Lane receiving a rapturous reception as he made way for Christian Saydee.
Norris was still looking sharp and even though he was beaten to the ball by Smith on the edge of the box, the keeper showed excellent reactions to keep out the substitute’s shot.
But Pompey were not done attacking themselves and Rafferty’s delivery into the box from deep could not be held by Button.
BISHOP calmly tucked the ball into the net, with referee Smith ignoring the keeper’s desperate pleas that he had been fouled.
That was not quite it for all the scoring, however, as when a Reading corner was only partially cleared, Savage slotted into the net.
It failed to dampen the raucous mood among the Fratton faithful, though, as Pompey strengthened their advantage over the chasing pack.
Pompey (4-2-3-1): Norris; Rafferty, Raggett, Shaughnessy, Ogilvie; Moxon, Pack (c); Kamara (Whyte 84), Lang (Martin 84), Lane (Saydee 73); Bishop (Yengi 84)
Goals: Lane 36, Pack 49, Lang 59, Bishop 84
Booked: Shaughnessy, Pack, Rafferty, Martin
Subs not used: Macey, Towler, Sparkes
Reading (4-2-3-1): Button; Yiadom (c) (Abrefa 74), Mbengue, Bindon, Mola; Wing (Savage 74), Craig; Azeez, Knibbs, Mukairu (Smith 53); Ehibhatiomhan (Elliott 74)
Goals: Savage 89
Booked: Wing, Mola, Azeez
Subs not used: Pereira, Monlouis, Wareham
Referee: Josh Smith
Attendance: 20,113 (1,987 away fans)