Oklahoma City Thunder guard Russell Westbrook has become the second NBA player in history to achieve a triple-double average for a season, though he fell just shy of breaking a 55-year-old record for most in a season. Westbrook joins Oscar Robertson, the only other NBA player to average a triple-double in a season. But he was modest about the achievement. “You could never say in a million years that I would think that was even possible,” Westbrook said late Friday. Westbrook had a rough night Friday in a game against the Phoenix Suns, falling just two assists shy of hitting his 42nd triple-double mark and breaking Robertson’s 55-year-old, single-season record for triple-doubles. The Oklahoma City Thunders lost 120-99 to the Phoenix Suns, prompting Westbrook to say after the game that he felt like he let his teammates down. Despite the loss, Westbrook still has three chances to get his 42nd triple-double, with two upcoming games against Denver and one against Minnesota.