WITNEY conceded a last-gasp try as they fell deeper into relegation trouble when losing 17-12 at fellow strugglers Chippenham.
The west Oxfordshire side are now 11 points adrift of safety with nine games remaining in South West 1 East.
Two Arron Lambourne penalties put Witney 6-0 up.
Harry Dyer crossed for the hosts as their lead was cut to 6-5 at the break.
Dyer went over again to put Chippenham ahead.
But two more penalties from the boot of Lambourne saw Witney edge 12-10 in front with seven minutes to go.
However, Matt Dickens crossed in the second minute of extra-time, Oli Alcorn converting, as Trowbridge snatched victory.
Banbury are nine points adrift of the play-off place after losing 18-5 at leaders Newbury Blues.
Bulls put in a battling performance, but could not stop their hosts, who preserved their 100 per cent record.
Kris Ford’s penalty put Newbury in front, before Harvey North’s try made it 8-0.
Banbury replied through Duncan Leese’s score.
- Duncan Leese scores Banbury's try during their defeat at Newbury Blues Video: Banbury RUFC
But Alex Millar and Tom Hunt crossed in the second half as Newbury secured victory.
Oxford Harlequins lost 36-20 at home to Trowbridge.
Johnny King’s try put the visitors 5-0 up, but the hosts levelled through Guy Fairburn.
A Connor James penalty saw Trowbridge retake the lead, only for Quins to go 15-8 in front when Martin Nutt and Jack Todd went over.
A penalty try saw the visitors make it 15-15 at the break.
Second-half tries from Scott Williams, Shai Bennick and Andrew Twinney, James converting, saw Trowbridge take a 36-15 lead.
Nutt crossed for his second as Quins picked up a four-try bonus point.
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