Pompey went six points clear at the top of League One with a comfortable 2-0 triumph over Southend
A Michael Turner own-goal and Jamal Lowe's glancing header - both in the first half - fired Kenny Jackett's side to an eighth successive victory in all competitions.
Luton leapfrogged Sunderland and moved second with victory over Fleetwood, after the Black Cats' game at Accrington was abandoned in the second half because of a waterlogged pitch.
The Blues didn’t have to wait long for their opener, breaking the deadlock after 11 minutes.
The Shrimpers failed to clear a free-kick and Ronan Curtis' left-wing cross was diverted into his own net by Michael Turner. who was under pressure from Oli Hawkins.
Kenny Jackett's side settled into their groove after taking the lead, with centre-half Matt Clarke spurning a glorious chance to double the advantage 12 minutes later.
Irishman Curtis fired in another delicious delivery, only for Clarke to head over unmarked from all of six yards.
Pompey were now in total command, grabbing a deserved second on 29 minutes.
Another fine Curtis cross picked out Lowe, whose superb flicked header found the bottom corner of the net via the post.
The hosts then had strong penalty appeals turned down five minutes before the break.
Gareth Evans' brilliant piece of skill saw him work some room before his cross appeared to strike the hand of Luke Hyam.
However, referee Lee Collins awarded a corner instead.
Southend were looking for a way back in and nearly had it 20 minutes from time.
Substitute Theo Robinson lead a quick counter-attack, before finding Stephen McLaughlin – but his strike was deflected wide.
The Blues should have put the game beyond the visitors five minutes later.
Lowe powered forward after being gifted possession by Dru Yearwood.
He then set up substitute Ben Close, who somehow fired wide from six yards.
But that miss did not matter as Pompey saw things out comfortably to extend their lead at the top of the table.