While Busby was in hospital recovering from the injuries he sustained in the air crash, his managerial duties were left to his assistant, Jimmy Murphy. After Busby recovered, he set about rebuilding his side, and within five years, in 1963, he had won the FA Cup for the first time in 15 years. This was followed up by two league titles in three years, and then the greatest prize in European club football, the European Cup. He continued as manager for one more year after this success, leaving his managerial duties to club trainer Wilf McGuinness. McGuinness struggled in his new post, however, and Busby was convinced to return for the second half of the 1970–71 season. However, he retired from football permanently that summer, and was succeeded that summer by Frank O'Farrell. O'Farrell's stay was short-lived, though, as his inability to control George Best's extravagances forced the board to sack him with three years still to run on his contract.