Will Eason's hard-hit 62 and older brother Robbie's patient 45 set Horspath on their way to their first victory of the season in Division 1.
Visitors Banbury Twenty had been heavily indebted to Ashley Pearson (90), who held his side's innings together as they posted 168 all out.
The home team were 32-3 when the Eason brothers came together, and despite a fightback led by Keith Arnold (3-57) that saw both dismissed, Horspath scraped together a four-wicket win with two overs remaining.
Horspath 25pts, Banbury XX 9
Oxford Downs skipper Wes Bartlett, who missed out on a century by two runs last week, finished the job at Bicester & North Oxford as his side romped to an eight-wicket win.
A patient 71 by Daryl Woods provided the foundation for Bicester's 180-9, which never looked enough.
Bartlett bludgeoned an unbeaten 101 and Richard West stroked 40 not out to take Downs up to fourth and leave Bicester rock bottom.
Bicester & North Oxford 5, Oxford Downs 25
All rounder Carl Thompson held his nerve to steer Cumnor to a four-wicket win over previously unbeaten Bletchley Town.
Put in to bat, Town made a slow start before Eddie Packard (40) injected some urgency, although he was also the guilty party in two run-outs.
Off spinner Umair Ghazali (3-34) was the pick of the home attack as the visitors were bowled out for 149.
Shahbaz Alam (43) and Ali Morteza (38) got Cumnor off to a flyer, and although there was a mini-collapse, Thompson (33no) took them from 106-6 to victory without further loss.
Cumnor 25, Bletchley Town 8
The resurgence of Shipton-under-Wychwood continued as they had the better of a draw with leaders Buckingham Town.
Put in to bat, Shipton racked up 240-8 thanks to Paul Hemming (61), Tim Senior (57) and Andrew Hemming (39).
Left-arm spinner Shaun Miller then varied his pace to good effect to take 5-49 as Town were restricted to 216-7, of which Brook Hatwell hit 63 and Jonny Cater 52.
Buckingham Town 9, Shipton-under-Wychwood 15
Wasim Mehmood took 5-26 for Oxford 2nd, but could not prevent Dinton piling on 258 before they were bowled out. Michael Sutliff was Oxford's main tormentor with 116.
In reply the hosts were in with an outside chance while Jamie Perkin was at the crease, but once he had gone for 73 and Mark Sheehan for 43 they had to settle for a draw on 207-8.
Oxford 2nd 12, Dinton 16