Twenty-year-old university student Thérin, who represented Jersey at the Commonwealth Games in Melbourne at discus, has had a superb week in what was always considered a secondary discipline behind discus and perhaps even shot putt.
Having set a new javelin personal best of 48.52 metres last week in the senior AAAs to finish fourth, the former Grainville and Millfield pupil this weekend shattered that mark with a massive 50.97 throw to claim U23 gold.
Thérin, representing the Channel Islands Athletics Club, received her gold from former Olympian javelin thrower Mick Hill, the coach to Jo Blair, who finished second.
Thérin, whose Island record of having won English Schools titles at two different events (discus and javelin) was matched earlier this month by fellow CIAC thrower Jamie Stevenson (discus and shot), is in action this coming weekend at the Throws Festival in Birmingham.