Jason Richardson
... that Jason Richardson is the only track and field athlete to have won both the 110 metres hurdles and 400 metres hurdles at a world youth championships?
... that <b id="mwCtg"><a class="mw-redirect" href="./Jason_Richardson_(athlete)" id="mwCtk" rel="mw:WikiLink" title="Jason Richardson (athlete)">Jason Richardson</a></b> is the only track and field athlete to have won both the <a href="./110_metres_hurdles" id="mwCto" rel="mw:WikiLink" title="110 metres hurdles">110 metres hurdles</a> and <a href="./400_metres_hurdles" id="mwCts" rel="mw:WikiLink" title="400 metres hurdles">400 metres hurdles</a> at a world youth championships?