Gareth Ainsworth made four changes to his side with Charles Dunne, Anthony Stewart, Kortney Hause and Josh Scowen all coming into the team.
Gary Doherty, Leon Johnson, Matt Spring and Sam Wood were the men to make way, while Charlie Horlock was cup-tied, with Lee Harrison taking his place. Former Chairboy Stuart Beavon started for the visitors, who were without the in-form Joe Garner and Paul Gallagher through suspension.
The visitors had a couple of early efforts, but didn’t come close to testing Matt Ingram, before Stuart Lewis had the Wanderers’ first chance, only for his sixth-minute volley from outside the area to fly harmlessly wide.
Ingram parried away Tom Clarke’s header in the 13th minute after the centre-back eluded his marker to meet John Welsh’s corner.
Ainsworth was forced into an early change after Dunne stayed down following a challenge, so Wood came on for the left-back.
Marvin McCoy fired wide from 25 yards in the 18th minute as Blues struggled to force their way into the area in the opening stages.
Wanderers came close to breaking the deadlock just past the half-hour mark when Hause met Scowen’s free-kick from the right, but the ball was hacked away near the line by Welsh.
However, it was the visitors who did strike first four minutes later and in some style. A long ball forward was flicked on by Beavon and Davies hit an unstoppable first-time effort from fully 25 yards that arrowed into the roof of the net.
Apart from Hause’s chance, Blues struggled to create much in the opening 45 minutes against a well-organised Preston defence. However, the visitors weren’t putting the Wanderers backline under too pressure much either and it was always going to take something special to break the deadlock, which Davies duly provided.
Neither side made any changes at the break and Hause headed Scowen’s corner over two minutes after the interval.
Knott flashed a left-footed strike wide after Morgan’s cushioned a header into the midfielder’s path, before Wednesday’s hero Stewart had a shot deflected over by PaulHuntington.
Davies could have and perhaps should have doubled Preston’s lead in the 67th minute when he headed over Chris Humphrey’s inch-perfect cross from six yards.
Knott came close to a superb equaliser two minutes later when he collected McCoy’s pass on the edge of the area and turned his marker before curling inches over the far post in front of the terrace.
That was to be the Sunderland loanee’s last involvement as he was replaced by Max Kretzschmar soon after.
Wood produced a match-saving challenge to deny Josh Brownhill after the winger had been cleverly played in on goal by Davies, but Wanderers failed to properly clear their lines from the resulting corner and Ingram had to come to the rescue, clawing away a header at the far post.
McClure came to Wycombe’s rescue 12 minutes from time when he cleared Clarke’s header off the line with Ingram beaten.
Ainsworth’s final throw of the dice came in the 81st minute with Steven Craig coming on for Morgan and Kretzschmar called Declan Rudd into action 60 seconds later when he instantly controlled Wood’s cross, before making room for himself and striking from the edge of the area.
No-one could get on the end of McCoy’s inviting cross as Chairboys pushed for a late equaliser, but great play from Wood earned the Blues a free-kick on the right, which the winger delivered for Stewart to head goalwards, only for Rudd to make a fine stop.
Wanderers: Ingram, McCoy, Dunne (Wood 14), Stewart, Hause, Scowen, Cowan-Hall, Lewis (c), Knott (Kretzschmar 71), Morgan (Craig 81), McClure.
Subs: Harrison, Doherty, Spring, Kuffour.
Preston: Rudd, Laird, Huntington, Clarke, Humphrey, Keane, Welsh (c), Brownhill (Byrom 90), Buchanan, Beavon, Davies.
Subs: Stuckmann, Croasdale, Hayhurst, Nicholson, Monakana.
Attendance: 2,249 (403 Preston)