Commonwealth Youth Games champion Aaron Sexton edged out Paralympic star Jason Smyth in a photo-finish to win the 100m at the Northern Ireland Championships.
Smyth led early on but was caught by the 17-year-old in the final stride as both crossed the line in 10.69 seconds at the Mary Peters Track.
Beechmount sprinter Davicia Patterson continued her fine early-season form by winning the women's 200m.
Patterson took .10 seconds off her personal best as she won in 24.75.
The 17-year-old, who achieved a World Junior Championship standard two weeks ago as she improved her 400m personal best to 53.64, was 0.26 ahead of DCH athlete Catherine McManus, who beat Patterson over one lap at last year's Northern Ireland Championships.
Patterson also finished ahead of Irish international 400m runner Sinead Denny, who was 0.01 behind runner-up McManus.
Northern Ireland Commonwealth Games athletes Emma Mitchell, Adam McMullen and Ben Reynolds all clinched victories.
Problems with the starting mechanism didn't help 110m hurdler Reynolds' hopes of a fast time as the race got off at the fourth time of asking with the Holywood man winning in 14.19 - 0.71 outside his personal best set in 2015.
With Kerry O'Flaherty an absentee, Mitchell eased to 1500m success in 4:17.93 as she finished over 10 seconds ahead of North Down's Rachel Gibson while long jumper McMullen produced an outdoor season's best of 7.79m.
Annadale Striders' Conall Kirk won the 800m 31 years after his father Mark clinched the second of his two Northern Ireland titles over the distance.
Kirk clocked 1:50.72 to finish 2.48 seconds ahead of club-mate Callum Crawford-Wallace.
Also in the middle distances, Springwell's Neil Johnston benefited from Danny Mooney's absence to win the men's 1500m in 3:57.90 while City of Derry's Conor Bradley took 5,000m victory in 14:57.59 as he held off Glaslough's Conor Duffy and City of Lisburn's Christopher Madden in a sprint finish.
Reality TV star Theo Campbell clinched his expected 400m victory after travelling over from England as he clocked 47.03 seconds to finish ahead of Craig Newell (47.36) and Andrew Mellon (47.59).
Campbell competes for the same Birchfield Harriers club as Commonwealth Games medallist Leon Reid, who was among the majority of Northern Ireland's Gold Coast team absent from Saturday's championships.