 Rooney akaita gore ra2011 risingafadzi, akadonhedzwa mumasemi-fainari emamita 400 paWorld Championships kuDaegu uye akapedza ari wechisere sechikwata cheBritain mumakwikwi e4 × 400 m relay. Muna 2012 Martyn akatanga zvakanaka, achimhanya 44.92s muna Kubvumbi paMt. SAC Relays muWalnut, California, nguva yake inokurumidza kubvira muna 2008. Rooney akakundikana kuchengeta chimiro ichocho achienda kumitambo yeOlympic yekumusha kwake, uye akabviswa mumakwikwi ehafu-fainari emamita 400, kumhanya 45.31s. Mumakwikwi ekupedzisira e4 × 400 metres Martyn akagamuchira baton ari pachinzvimbo chechitanhatu uye akamhanya 44.1 yechipiri anchor gumbo, asi aisakwanisa kupfuudza Deon Lendore weTrinidad uye saka akapedza wechina. 