DEION SANDERS was host of "Saturday Night Live." In one skit, he portrayed the Reds Player Rep addressing a group of baseball players on the strike (NBC, 2/18). JIMMY JOHNSON was on ABC's "Coach" last night (ABC, 2/20). BILL CLINTON attended last night's Georgetown-Villanova game, and was interviewed on ESPN. On seeing a sign that said Clinton/Vitale '96, Clinton said, "That may be Al Gore's idea" ("Big Monday," ESPN, 2/20). Nuggets G.M. BERNIE BICKERSTAFF will take over head coaching duties from GENE LITTLES, who will remain as an assistant. Bickerstaff will also become president of the team, succeeding TIM LEIWEKE, will will oversee team owner Comsat's plans for a new arena (Mult, 2/21)....JOSE CANSECO is breaking from agent DENNIS GILBERT and starting his own agency (USA TODAY, 2/20).