Fluke goal downs Blues
But James Wesolowski soon equalised and the Shrews – who have dropped just two points at home this season – grabbed a second half winner when Connor Goldson’s cross drifted into the net.
Pompey were undone by a freak goal as Shrewsbury fought from behind to secure victory at Greenhous Meadow.
Andy Awford stuck with the same side that beat Stevenage at Fratton Park earlier in the week.
Pompey failed to properly deal with another set-piece on 13 minutes, however, and Wesolowski drove the loose ball through a sea of bodies and into the net.
The hosts tried to hit back, but James Dunne made a brave block to stop Wesolowski converting a corner.
WALLACE stepped up to take the penalty and emphatically slammed it past Leutwiler to send the large travelling contingent wild with delight.
The wing-back needlessly stuck his arm up to block Craig Westcarr’s corner and referee Dean Whitestone immediately pointed to the spot.
But the Blues did not have to wait much longer to score, with Mickey Demetriou literally handing them the advantage.
Paul Robinson met Ricky Holmes’ cross and looked like he would convert from close range, only for Shrewsbury keeper Jayson Leutwiler to somehow claw the ball to safety.
Pompey made a strong start and it took a stunning save to stop them forging ahead with less than a minute on the clock.
Jean-Louis Akpa Akpro should have provided the home fans with a boost on 38 minutes, only to glance Jack Grimmer’s cross wide from close range.
But such a frantic start did not herald a half full of clear-cut chances, with the game soon losing much of its zip.
Shrewsbury 1 Pompey 1 Half Time:
And that was the closest either side came to securing an interval lead as the half limped to a conclusion.
The Blues seemed happy to let their opponents keep hold of the ball and soak up any pressure, however, with Paul Jones being well protected.
Wallace then drew a regulation save from Leutwiler at the goalkeeper’s near post, but it was Shrewsbury who were controlling possession.
Westcarr wasted a decent opportunity by mis-controlling the ball before Dunne fizzed a low effort narrowly past the post.
Pompey began the second half as they had the first – by mounting an attack.
But they were dealt a huge blow soon after when Goldson’s attempted cross instead looped over Jones, grazed the underside of the crossbar and nestled in the net.
Another switch followed on 70 minutes as the Blues sacrificed a striker, with Storey making way for Nigel Atangana.
Awford had made his first substitution a few moments earlier, freshening up his front-line by replacing Westcarr with Ryan Taylor.
Pompey’s keeper was called into action on 63 minutes, though, parrying clear Bobby Grant’s free-kick before Robinson reacted quickest to block the follow-up.
Awford responded by calling for another forward from the bench and Patrick Agyemang came on for Holmes.
But Pompey almost fell further behind on 80 minutes, with the unmarked Akpa Akpro contriving to blaze high over the bar.
And they were unable to find a late equaliser as the hosts held on to claim all three points.
Leutwiler; Goldson (c), Grandison, Knight-Percival; Grimmer, Grant (Lawrence 74), Woods, Wesolowski (Clark 77), Demetriou; Akpa Akpro, Collins (Mangan 70) Shrewsbury (3-5-2):
Jones; Devera, Robinson, Chorley (c), Shorey; Wallace, Dunne, Hollands, Holmes (Agyemang 79); Storey (Atangana 70), Westcarr (Taylor 59) Pompey (4-4-2):
Halstead, Ellis, Griffith, Vernon Subs not used:
Wesolowski 13, Goldson 72 Goals:
Wallace 3 (pen) Goals: 5,515 (835 Pompey fans)Attendance:
Dean Whitestone Referee:
Poke, Ertl, Butler, Barcham Subs not used:
Dunne, Robinson Booked: