Witney reached the semi-finals of the Oxfordshire Cup after an impressive 22-7 victory over Oxford University Greyhounds at Hailey Road.
They will now visit Oxford Harlequins, who saw off Chinnor 2nd 6-3 last month.
Fly half Henry Lamb kicked Witney ahead with a penalty.
No 8 Charlie Bennett had a try disallowed before the break.
Greyhounds hit back when wing Dom Oboh’s break allowed lock Graeme MacGilchrist to score.
Fly half Jack Davidson converted for 7-3, but Witney came back strongly.
Wing Arron Lambourne went over twice in five minutes, both times having been fed by scrum half Gareth Campbell.
Lamb converted the first of these and a late try from Bennett, who scored via a rolling maul.
Alchester gave Henley Bulls, the National 1 club’s second team, a walkover.
Henley will play Banbury or Grove, who contest the last quarter-final at Bodicote Park tomorrow night after their original clash was postponed due to waterlogging.