Rangers overcame the odds - and a snow blizzard - to see off Championship leaders Birmingham City with only 10 men.
Mikele Leigertwood was sent off on the stroke of half-time for raising his foot at City's Lee Carsley, but caretaker boss Gareth Ainsworth survived his first ordeal by overseeing a 1-0 win.
Italian Samuel Di Carmine struck a spectacular winner after 54 minutes from outside the area and then Rangers defended resolutely. Radek Cerny was seldom troubled as City surrendered top spot to Wolves.
Victory avenged a 1-0 defeat to Birmingham at St Andrews earlier this month and lifted the Rs up to seventh - just outside the play-off places.
"Those boys were outstanding and the commitment they've shown for me tonight is the reason we've won this game," Ainsworth said. "Everyone's pulling tight and back each other."