 Pierce akaisa 7th achikwikwidza pamwero mukuru pa2015 US Championships uye akasarudzwa kukwikwidza pa2015 World Junior ChampionshipsmuTallinn, kuEstonia. Akanga ari wechi19 mumakwikwi maduku uye wechi22 mumakwikwi akasununguka, akapedza ari wechi19 mumakwikwi ose. 