Women's compounder Rikki Bingham and men's recurver Ashe Morgan booked their places at the Nottingham grand day out on 1 September after second stage wins of the year. Abbie Fisher won her first ever National Series stage, and has shot her way into contention in women's recurve.
Naomi Folkard, who missed this event following her World Games gold medal heroics on Friday, is the only women's recurver guaranteed her Grand Final place, setting up a thrilling finale at Lilleshall last weekend.
Abbie will certainly be eyeing up a trip to Nottingham after her superb performance at Oxford, with Nicky Hunt second, and Amy Oliver third.
There are still two places up for grabs in the men's compound, with Michael Caue and defending champion Adam Ravenscroft now guaranteed their Grand Final places, in a division that is seeing established names like Chris White, Duncan Busby and Liam Grimwood now having to pull out all the stops at Lilleshall.
But there will be just one place on offer in the men's recurve and women's compound.
Rikki's victory means she will join Dani Brown and Andrea Gales at Nottingham, with the final place decided at Lilleshall next weekend.
Ashe's second win of the year means he will join defending champion Larry Godfrey and World Games bronze medalist Alan Wills in Nottingham. Like compounder Michael, it will be his first Grand Final appearance.
On course for a first appearance too is Michael Judd, from Essex, who was third this weekend, with the help of a fellow archer who loaned him archery limbs, after his own gave up on him.
"That gesture underlines the great camaraderie of a National Series shoot," said National Series organiser Jon Nott. "Michael shot superbly, and if he repeats that next weekend then he too will be at his first Grand Final, which would be a tremendous achievement.
"Oxford archers organised a magnificent shoot, and I can't compliment them enough for a fabulous weekend.
"Unfortunately they couldn't influence the weather, and the wind played havoc with us. But, as ever, archers proved a hardy bunch and coped admirably."
Stage five of the National Series takes place at Lilleshall this coming weekend, with the Grand Final at Nottingham's Wollaton Hall three weeks later.
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