SYDNEY (AP)- A rugby league player has been banned for eight games after using a racial slur against a rival during the Australian NRL’s season-opening round in Las Vegas. A National Rugby League judiciary on Monday rejected a claim by Sydney Roosters forward Spencer Leniu that he didn’t know he was racially vilifying Ezra Mam when he directed the slur at the Brisbane Broncos player in the March 2 match. The 23-year-old Leniu has Samoan heritage and has represented its national team. He was born in New Zealand and moved to Australia as a child. He signed for the Roosters this season after playing for the defending champion Penrith Panthers since 2019. Mam is an Indigenous Australian who has Aboriginal and Torres Strait Islander descent. Leniu issued a public apology…