Wycombe secured their first home win for over a month with a convincing 4-1 victory at struggling Fleetwood.
Lee Johnson, who took over from Scott Brown last month, had led the Cod Army to back-to-back wins without conceding.
But they were completely blown away by the on-song Chairboys as Dale Taylor's double, Freddie Potts and Luke Leahy secured victory at Highbury.
Jack Marriott's effort was a mere consolation before the hosts' day was compounded by Ben Heneghan's second-half sending off.
Northern Irish striker Taylor opened the scoring with a looping header from the edge of the six-yard box from Josh Scowen's cross in the 20th minute.
Potts doubled the advantage with his second goal for the club with a fine touch and finish, completing a great team move, 14 minutes later.
It was three before the break as Potts turned provider for Taylor to slot home.
Marriott pulled one back as he diverted home Junior Quitirna's cross.
But any hopes of a miracle comeback were dashed moments later when Heneghan tripped Brandon Hanlan who was racing through.
Leahy added gloss from the resulting free-kick as he bent it into the top corner.