August Belmont Jr. sold Friar Rock shortly after his win in the 1 miles Saratoga Cup. New owner John E. Madden brought him to stand at stud at his Hamburg Place farm in Kentucky. Only a minor success as a sire of racers, Friar Rock did produce the noteworthy runner Pilate, who in turn was the sire of Eight Thirty. Pilate himself won 24 of his 44 starts. Friar Rock's other progeny included Rockminster (winner of the Pimlico Cup Handicap), Flat Iron (raced 107 times and won the Hawthorne Handicap), and Polydorus (won the Tremont Stakes). Friar Rock proved to be a good broodmare sire and on five occasions was in the top ten on the annual broodmare sires' list. One of his best-known daughters was Friar's Carse, the United States' Champion Two-Year-Old Filly and dam of War Relic.