Multiple Grade 1 winner Polish Navy, sire of 1993 Kentucky Derby winner Sea Hero, has died at age 27.\r\nThe pensioned Danzig stallion was euthanized Thursday morning at the Old Friends equine retirement facility in Georgetown, Ky., due to complications to a hip injury he suffered last month.\r\n&ldquo;Polish Navy injured his hip several weeks ago and was taken to Hagyard&rsquo;s, where he received excellent diagnostic care,&rdquo; Old Friends founder and president Michael Blowen said, referring to the Hagyard Equine Medical Institute in Lexington. &ldquo;Unfortunately, he just never recovered. Dr. Doug Byars visited with this great old horse several times and, in consultation with Old Friends, advised us that Polish Navy&rsquo;s time had come.&rdquo;\r\nPolish Navy won the Champagne and Cowdin and 2, then returned to take the Woodward at 3 in 1987. He also won the Grade 2 Jim Dandy and placed in four other stakes: the Travers, Marlboro Cup Invitational, and Dwyer Stakes, all Grade 1&rsquo;s, and the listed Riva Ridge.\r\nAn Ogden Phipps homebred, Polish Navy was out of the Tatan mare Navsup and was her only stakes winner. He was a half-brother to Grade 3-placed Judge Advocate.\r\nPolish Navy had resided at Old Friends since 2009.\r\nIn addition to Sea Hero, who also won the 1992 Champagne and 1993 Travers, Polish Navy sired Grade 1-winner Ghazi, Grade 1-placed Law of the Sea, and such foreign champions as Godspeed and Polish Warrior.