Wanderers are just one more win away from a first Wembley appearance in 12 years after a Jon Dadi Bodvarsson winner took them into the semi-finals of the Papa Johns Trophy.
It wasn’t always pretty stuff as Ian Evatt’s men had to show their gritty side on a tricky saturated surface to get past their League One rivals in the first of two meetings between the sides in five days.
But a sixth clean sheet in seven games coupled with Bodvarsson’s 17th-minute strike was enough to get the job done and keep alive hopes of silverware at Wembley in early April.
Wanderers made six changes to their starting line-up following Saturday’s draw with table-topping Plymouth with Ricardo Almeida Santos among those charged with setting the Whites on their way towards the last four.
It was a welcome return for the club captain following illness in his first appearance since the Whites knocked out Barrow in the first knock-out round of the competition.
And he had a hand in the opening goal with just over a quarter of an hour gone as Wanderers took the lead.
A clearing header from Santos went as far as Dion Charles, although the striker did most of the work in superbly spinning away from two defenders before releasing Bodvarsson to run through and slot home his third goal of the cup run and eighth in total for the season.
Not for the first time Charles was proving too much for a defence to deal with as he punched regular holes in Pompey’s back line as Wanderers threatened a second on a number of occasions while they were on top.
While that goal didn’t come, the visitors weren’t out of the game as they enjoyed their best spell towards the end of the first half.
But just before the break it was Wanderers who almost struck again to take firmer control with Owen Beck seeing a shot brilliantly blocked by Pompey skipper Sean Raggett after the visitors had been pegged back in their penalty area.
Wanderers needed a cushion with Portsmouth also starting the second half on the front foot as they chased an equaliser.
And with just over an hour gone Evatt made his first changes in a bid to regain the momentum in an increasingly scrappy encounter as he swapped wing-backs.
Randell Williams was one of those introduced and the recent recruit made an immediate impression with a couple of penetrating runs and dangerous deliveries from the left flank.
Kyle Dempsey and Amadou Bakayoko followed from the bench to help Wanderers get over the line and when Williams clipped in another inviting ball, Bakayoko headed just wide with 10 minutes to go.
With Wanderers going for the kill, Bakayoko then saw an effort well kept out by Josh Griffiths as he just stopped the ball going over the line at his near post.
But with Pompey desperate for a goal they threatened at the other end as substitute Colby Bishop chipped wide after James Trafford had been forced to head clear following a break-away which followed an apparent foul on Williams.
Trafford hadn’t been over-employed but with 90 minutes on the clock he had to make a smart save to beat away a shot from substitute Recco Hackett to keep at bay the prospect of penalties.
And with that threat averted Wanderers were there with a place in Saturday’s semi-final draw to come on the back of what’s now a seven-match unbeaten sequence.
Wanderers: Trafford; Toal, Santos, Johnston; Sadlier (Bradley 63), Williams, Sheehan (Dempsey 74); Beck (Williams 63); Kachunga; Bodvarsson (Morley 78), Charles (Bakayoko 74). Substitutes: Aimson, Lee.
Portsmouth: Griffiths; Swanson (Freeman 63), Raggett, Ogilvie, Hume; Pack, Morrell (Thompson 63); Curtis, Koroma (Jacobs 63), Scarlett (Hackett 72); Pigott (Bishop 72). Substitutes: Oluwayemi, Tunnicliffe.
Referee: Robert Madden
Attendance: 4,413 (304 Portsmouth)