 His most notable result was at the 1851 London tournament, in which he defeated the celebrated British player Howard Staunton in the play-off for third place.He was accused by Staunton of taking an average of 2½ hours per move during some matches, a strategy thought to cause opponents to lose their focus on the match.According to Staunton, following a particularly dilatory performance by Williams in the London 1851 tournament, a 20-minute per turn time limit was adopted for standard play the next year.