Pompey moved up to third in the League One table with a 2-0 victory at Shrewsbury Town.
Goals either side of half-time from Ben Close and Brett Pitman ensured the Blues leapfrogged Sunderland in the race for automatic promotion.
And it ensured Kenny Jackett’s troops head into the Checkatrade Trade final next Sunday on the back of a success.
Pompey started slowly and were fortunate not to find themselves behind in the fourth minute.
Fejiri Obeknabirhie squared a cross along the six-yard box but Shaun Whalley couldn’t quite get there.
And the Blues were indebted to Craig MacGillivray on 15 minutes when he made a superb save to thwart Whalley’s stinging effort onto the post.
The Shrews continued to dominate and Scott Golbourne thought he’d broken the deadlock in the 24th minute but Lee Brown made an excellent block to thwart the goalbound effort.
Jackett’s men finally started to get a foothold in the game, with Gareth Evans having a shot saved by home keeper Steve Arnold in the 29th minute.
Four minutes later Close fired a shot that just missed the top corner.
But it was the Southsea midfielder who broke the deadlock in the 40th minute.
Lee Brown’s effort was adeptly kept out by Arnold but the rebound fell to Close, who kept his head over the ball to stroke home a left-footed shot.
Sam Ricketts’ side started the second half the better, although Pompey limited them to few clear-cut chances.
And the Blues went agonisingly close to doubling their lead in the 63rd minute.
Brown’s cross picked out substitute Oli Hawkins in the six-yard box but his effort deflected off Omar Beckles before bouncing onto the crossbar.
And it was the striker who again almost added a second.
Brown was the provided when he stood up a cross to the back post and Hawkins’ downward header was parried clear by the diving Arnold.
Shrewsbury pushed for an equaliser and MacGillivray was forced to repel Ollie Norburn’s 25-yard free-kick which fizzled straight through the wall.
Pompey needed breathing space – and it arrived 11 minutes from full-time in slightly fortunate fashion.
A defensive mix up between Arnold and Beckles allowed Pitman to feed in Hawkins.
The skipper carried on his run into the box, with Hawkins sliding a ball across for Pitman to finish coolly from close range.
The Shrews searched for a way to get back into the game, but the Blues remained resolute to collect a clean sheet.
With Sunderland not in action, Pompey jumped above their promotion rivals ahead of their Wembley meeting next Sunday.
And Jackett’s side stay four point adrift of second-placed Barnsley with seven games remaining.