BOSSIER CITY, La. - Jockey Shane Sellers will be out two to three weeks after injuring a disc in his back working a horse during morning training hours at Louisiana Downs on Friday, according to his agent, Anthony Martin. \nSellers was off his mounts on Friday, and was scheduled to ride Uno Mas in the Grade 2, $750,000 Super Derby here Saturday. \n"He'll be out two to three weeks," Martin said Saturday. "He was breezing a horse yesterday and it jerked on him the wrong way. We probably won't see him the rest of the meet."\nMartin said the injury simply requires rest. He said Sellers remains on schedule to ride the Fair Grounds meet that opens Nov. 6. He said Sellers could return to riding the second week of the Delta Downs meet that opens Oct. 14.\nSellers, a career winner of more than 4,000 races, returned to the saddle in July after a 4 1/2-year layoff. He is winning races at a 25 percent rate. He began his comeback at Evangeline then moved his tack to Louisiana Downs when that meet ended Sept. 7.