LITTLEMORE scored five tries to defeat hosts Faringdon 31-13 in their first-round clash.
Mike Shelley, Darren Massey, Darrell Rendell, Jonny Williams and Ben De’figuieredo all crossed for the visitors.
De’figuieredo added three conversions as Littlemore earned a semi-final at home to Blue Boar.
Faringdon trailed 24-6 at the break, with Darren Clark kicking two penalties.
No 8 Will Thompson bagged the hosts’ only try from a pushover effort, Clark converting.
Wheatley will host Chipping Norton in the semi-finals after winning 22-17 at Didcot.
Didcot led 12-10 at half-time, thanks to tries from Ronnie Booth and John Madley, Paul Costello converting one.
Ben Loughlin scored a try from the final play, converted by Costello.
Pete Mitchell, James Butler and Ben Kelsey crossed over for Wheatley, with Jason Laman converting two and adding a penalty.
Centre Will Sandbach and wing Ben Nelson scored two tries apiece as Blue Boar hammered Bicester, who had to field four forwards in their backline, 48-22.
Flanker Harry Osborn, scrum half Dale Scott and full back Chris Sandbach also touched down for Boar, with fly half Oscar Matthews kicking 18 points and Will Sandbach adding one conversion.
Scrum half Steve Risbridger, full back Mike Harris and centre Alex Benjamin scored Bicester’s tries.
Fly half James Blake kicked two conversions and a penalty for the hosts.
Semi-finals: Wheatley v Chipping Norton, Littlemore v Blue Boar. Ties to be played on December 1-2.