Max Kretzschmar's first-half penalty gave Wycombe their first victory at Adams Park since mid-October as they recorded a 1-0 win over Sky Bet League Two leaders Chesterfield.
Kretzschmar gave Spireites goalkeeper Tommy Lee no chance from 12 yards 10 minutes before the interval after captain Ian Evatt had clumsily handled Matt McClure's cross.
In addition to ending their poor home record, it was only the fifth time the Chairboys had scored in 11 games since Christmas Day, and it also gave them their first victory since December.
Former Arsenal striker Anthony Jeffrey volleyed wide on his full Football League debut and Matt Bloomfield shot tamely at Lee from six yards as the goal-shy hosts looked to double their advantage.
Evatt thought he had made amends for conceding the decisive penalty as he headed in Gary Roberts' free-kick just after the hour mark, but he was adjudged to be offside.
Jay O'Shea also came close while Roberts had his 20-yard effort saved by Matt Ingram.
But the Spireities, who had manager and birthday boy Paul Cook sent off by referee Dean Whitestone in first-half stoppage time for dissent, fell to only their second league defeat of the calendar year.