Cliff Alexander was such a star H.S. basketball recruit … one cop remembered him during the former NBA player’s gun arrest this month — and the interaction was all caught on police video obtained by TMZ Sports. Alexander was pulled over at around 9:30 PM CT on May 6 in Chicago, Ill. after cops say he blew through a stop sign … and shortly after, one officer realized who exactly he had detained. “Oh, you’re that hooper!” the cop said, before asking him about his high school recruiting ranking.