ɪn ɹˈaʊnd ɪlˈɛvən ʌvðə tˈuː θˈaʊzənd fˈɪftiːn ˌɛnˌɑːɹɹˈɛl sˈiːzən, kˈuːpɚ kˈæptɪnd ðə kˈaʊbɔɪz fɚðə fˈɜːst tˈaɪm ɪnðə sˈaɪdz ˈeɪt zˈiəɹoʊ vˈɪktɚɹi ˌoʊvɚ ðə wˈɛsts tˈaɪɡɚz.
In Round 11 of the 2015 NRL season, Cooper captained the Cowboys for the first time in the side's 8–0 victory over the Wests Tigers.