Oxfordshire's Harrison Ridge slipped to a 6-2, 6-2 defeat to 14 & under top seed Jack Molloy in the Grade 2 Winter National tournament in Bolton.
Ridge, from Wargrave, stormed to victory in the first two rounds, but his Buckinghamshire rival proved too strong in the last-eight clash.
Unseeded Josh Ridley, from Oxford Sports beat the top three seeds on the way to winning the 18 & under boys event at the White Horse Grade 4 tournament in Abingdon. Jess Lythgoe, playing at her home venue, followed up her triumph in the 16 & under crown last week by lifting the 14 & under title.
Oxfordshire 16 & under boys and girls finished third and fourth respectively in their 12 Counties Tournament debut at Corby.
The girls got off to a great start with a 3-1 win against Northamptonshire, only for the boys to lose their opener 4-0.
Both teams found Cheshire too tough, with the girls losing 3-1 and the boys 4-0.
In the final round, Oxon girls lost 3-1 to Bedford as did the boys, for whom John Balshaw won their only rubber 4-2, 4-2.