Chris Westwood and Kevin Betsy were the heroes as lowly Wycombe notched their first win in 14 attempts to ruin Millwall's vintage run at the Den with a 2-0 victory.
The Lions had not lost in 14 home games heading into the clash but Westwood and Betsy popped up after the break to seal Wycombe boss Gary Waddock's first win since taking charge.
The home side had the best of the first half but the opening chance fell to Wycombe after 16 minutes but Westwood headed Scott Davies' cross over.
And just two minutes later another golden chance was wasted - this time Lions skipper Paul Robinson heading wide.
Jason Price was sent through by Marc Laird on the half-hour but his hesitation allowed the Wycombe defence to scramble clear.
Millwall roared out of the blocks after the break only to be dealt a sucker punch after 56 minutes when Chris Westwood rose highest to head home a John Mousinho corner from 10 yards out.
And with the Lions pressing the Chairboys sealed the points 18 minutes from time when Davies slipped Betsy through and the former Southend midfielder ran 40 yards before converting.
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