Jockey agent Bob Hack, whose clients included Laffit Pincay Jr. and Roberto Gonzalez, died at his home in Pleasanton, Calif., on Thursday morning. Hack, 81, was suffering from emphysema. A native of St. Louis, Hack was raised in San Francisco where he was introduced to the racetrack by his father, Victor, a foreman for Hall of Fame trainer William Molter, and uncle, Clyde Turk, a jockey and trainer. After a stint in the Navy as a submariner, Hack returned to the track as a trainer before beginning as a jockey agent for Dick Beasley. Among the jockeys he booked mounts for were Laffit Pincay Jr., Charlie Tohill, Bobby Jennings, Juan Gonzalez, Bill Delia, Joe Judice, Randy Schacht, Chad Schvaneveldt and Roberto Gonzalez. Hack, who also served as a mutuel clerk, retired as an agent after Gonzalez was injured in a 2009 spill.Hack is survived by his wife, Shirley, daughters, Kim Chanu and Kim Munoz, and a son, Robert Jr.