Aston Villa have recovered from an early setback to lead 2-1 after 45 minutes at the Madejski Stadium.
Reading started quickly and were almost ahead after just three minutes when Adam Le Fondre forced Brad Guzan to scramble clear his header from close range.
Villa struggled early on but nearly broke to deadly effect five minutes later when Christian Benteke saw his angled header come back off the crossbar.
Matthew Lowton was booked for a cynical challenge on Jobi McAnuff inside 12 minutes as Reading threatened in wide areas.
Hal Robson-Kanu drove a strike from range inches wide as the Royals started to take control of the match before the interval.
Reading took the lead in comical fashion soon after as Nathan Baker lashed into his own net after failing to deal with a cross from McAnuff.
Villa responded quickly and equalised when Andreas Weimann crossed for Benteke, who turned home with the aid of a late deflection.
The turnaround was complete just before the break when Gabriel Agbonlahor scored his seventh of the season on the rebound from close range.