Paul Cook’s table topping Chesterfield slipped to only their sixth league defeat of the season after a lacklustre performance at Adams Park.
Max Kretzschmar’s first half penalty for Wycombe Wanderers, after Ian Evatt was penalised for handball, was all that separated two sides from either ends of the table.
The Spireites could be accused of suffering from a hangover after the midweek excitement of securing a Wembley date in the Johnstone’s Paint Trophy.
But the manner of the defeat to lowly Wycombe would give Cook, who was 47 on Saturday, a headache no amount of pain relief tablet could cure.
Chesterfield couldn’t find any rhythm and were dragged in to a kick and rush approach that suited Gareth Ainsworth’s Chairboys, ironically, down to the ground.
Wycombe’s defiant defensive display, led by Leon Johnson and Gary Doherty, combined with a flurry of controversial decisions frustrated the Spireites camp.
Those annoyances boiled over just before half-time when Cook was sent to the stands for dissent after continuing his protests with referee Dean Whitehouse.
Following the game, Cook said the day served as a reminder to his Wembley-bound players of how difficult a league it is to achieve promotion from.
He said: “This league is a very unforgiving one. The minute you think you’ve cracked it you haven’t and we’ve got a really good lesson today in that.
“There’s nothing in the game. The referee has given a penalty and that’s his decision. Really we should have been speaking about drawing nil-nil.
“Unfortunately for us, we’ve got nothing. I felt that he (Mr Whitehouse) was losing the game. It was becoming like who could have the most fouls.”
The match offered little in goalmouth action. Wycombe threatened and, aside from the penalty, conjured up one effort on target which came in the second half.
Chesterfield had an Evatt header ruled out for offside before Gary Roberts tried his luck from distance in the 87th minute, which was comfortable for Matt Ingram.
“It’s unfortunate,” said Cook. “You’ve got to give Wycombe credit they worked their socks off for victory. They covered every blade of grass on the pitch.
“We’ve been on good runs and we’ve had a harsh lesson today that there’s a long way to go and we’ve got to be at it to compete to get results out of games.
“We’ll analyse our own performance because that’s a long way from us today.
“Every Chesterfield fan - and they travelled in great numbers again today - will know we’re a lot better than that.”
He added: “We never got any tempo in the game. Most managers will blame referees but we’ll have none of that at our club. We’ll try to have some good manners. ”
Chesterfield remain top on goal difference alone after second placed Scunthorpe United swept aside Portsmouth 5-1. Rochdale are hot in their heels in third after a 1-0 away success at Exeter City.
Not one of the chasing pack could manage a win while Newport in eighth were beaten by the Spireites’ Tuesday night opponents Cheltenham Town.