Gareth Ainsworth’s men had the better chances throughout, seeing visiting keeper Trevor Carson make fine saves to thwart Matt McClure and home debutant Reece Styche.
However, the game swung on a controversial penalty awarded when Wes Fogden tripped over Gary Doherty’s outstretched leg and Taylor dispatched the spot-kick.
Doherty thought he’d salvaged a point in stoppage time but the referee spotted a foul and the Blues were left to reflect on the chances that passed them by.
Pompey requested a change of ends at kick-off and attacked towards the Dreams Stand in the first half, home to a large vocal following who were in no mood to let their recent plight dampen their spirits.
As the rain began to accelerate, it was Wycombe who came closest to opening the scoring on 7 minutes when Matt McClure hit an opportunistic effort from distance, and keeper Trevor Carson took no risks on a slippery surface by turning it behind for a corner.
The hosts were enjoying an impressive start, as they had done on both visits to Fratton Park earlier in the season, although the pace of Andy Barcham and Wes Fogden on the counter-attack gave them food for thought defensively. The former had a shot blocked on 16 minutes before the latter delivered a dangerous cross from which neither Ryan Taylor nor Jake Jervis could benefit.
McClure was full of running up front for the hosts and, moments after heading Sam Wood’s inviting cross wide under pressure, the striker sent a stinging shot towards the bottom corner only for Carson to keep it out with a strong left hand.
Carson was at it again following the resulting corner, flying to his right to punch away Reece Styche’s volley when the ball fell kindly for him 12 yards out.
It was probably the only clear-cut chance of the half but Wanderers would have perhaps felt unlucky not to lead at the break, drawing applause from their fans as the two teams disappeared down the tunnel.
There were no changes at the interval but it took just four minutes for the deadlock to be broken in controversial style. Wes Fogden played a pass across the box and his momentum took him over the outstretched leg of Gary Doherty, but with no appeals forthcoming from the visitors, referee Charles Brakespear pointed to the spot and Ryan Taylor stroked home the penalty.
It was harsh on the home side who could have gone further behind had Jake Jervis not made a hash of a near-post effort from Fogden’s cross moments later.
Josh Scowen then looked to replicate his goalscoring exploits from the weekend with a snapshot from the edge of the area, but Carson was equal to it, getting his body behind the ball as it came through a crowd of players.
The midfielder found himself in the wrong place at the wrong time on 56 minutes when Leon Johnson shot goalwards from McClure’s knockdown, only to see Scowen block his shot inadvertently and the danger was cleared.
It wasn’t quite one-way traffic and the visitors almost stretched their lead when a smart attacking interchange allowed Barcham to fire a low ball across the frame of the goal, but Jervis couldn’t convert when sliding in at the back post.
Wanderers might have felt it wasn’t going to be their night when McClure’s looping header bounced against the post, onto the line and was somehow kept out despite a bundle of bodies all converging in the six-yard box just after the hour-mark.
Ainsworth changed his wide midfielders soon after, bringing on Matt Bloomfield and Anthony Jeffrey for Nick Arnold and Sam Wood, but Pompey gradually took the sting out of the game and thwarted the Blues’ attacking tempo.
Wycombe refused to accept defeat and created a number of crossing opportunities, but the ball never fell kindly at the feet of a man wearing light and dark blue.
As the game reached its closing stages, Pompey dug deep to find enough composure to keep the Blues at bay, but they still had to survive a late scare. From Marvin McCoy’s deep throw, Gary Doherty bundled home but appeared to use an arm in the process, which was spotted by the ref and the goal was ruled out.
Wycombe: Ingram, McCoy, Mustoe, Doherty, Johnson, Arnold (Bloomfield 66), Lewis, Scowen, Wood (Jeffrey 66), McClure, Styche.
Subs: Horlock, Hause, Stewart, Kretzschmar, Kuffour.
Portsmouth: Carson, Alfei, Painter, Devera, Chorley, Barcham, Padovani, Shorey (Ertl 90), Fogden (Holmes 77), Jervis (Agyemang 87), Taylor.
Subs: Smith, Bradley, Racon, Wallace.