Guitar Hero : Warriors of Rock and DJ Hero 2 sold only 86,000 and 59,000 copies , respectively , in North America during their first week on the market .
Guitar Hero : Warriors of Rock and DJ Hero 2 sold only 86,000 and 59,000 copies in North America during their first week of sales , respectively , a sharp contrast to Guitar Hero III which had seen nearly 1.4 million units in its first week in 2008 .