Chichester teen Josh Dunne was the standout performer as the best of Sussex went head-to-head in the under-13 county championships at Withdean Stadium in Brighton.
Five athletes from Chi Runners took part in the competition, which featured one of the strongest groups of athletes in recent years.
800m runner Dunne led the way, knocking a whole five seconds from his previous best with a time of 2.20.
With a successful season in the National Youth Development League over 800m and the Sussex League over 600m behind him, Dunne used his experience to run a controlled race and was too strong for his rivals to win with two seconds to spare.
Also in the middle distance races were twins Laila and Lillie Hellyer, who will still have another year in the age group in 2020.
Laila finished a creditable sixth in the 1500m in 5.23.07 while Lillie was seventh in heat one of a very competitive 800m in 2.42. Alice Waterworth was sixth in heat two in 2.51.8 as well as notching up a good long jump mark of 3.56m.
The fifth Chichester athlete on view was Grace Bishop, who teamed up with Waterworth in the hurdles as well as finishing in ninth place in the high jump.
Elsewhere, a squad of just 11 athletes represented Chichester in the second under-15 Sussex League match of the season at the K2 in Crawley. They did the club proud, to finish third out of the six clubs with only Crawley and Horsham ahead.
On the track, new member Josh Miller impressed in both sprints with two second places in 12.8 and 26.3sec for the 100m and 200m.
Following his exploits on the track, Miller teamed up with Hugo Martell to form a winning partnership in the shot, throwing 10.43m and 10.31m respectively.
Martell continued his fine season in winning the discus by more than four metres with 26.93m and coming a close second in the hammer.
For the girls, Chi had a strong throwing contingent, Lulu Millen making a good trio on the discus. Millen also threw well in the javelin with a second place in the A string at 22m, a result matched by Tatum Anwyl in the B squad.