 Complete the following phrase:  Best made his First Division debut, aged 17, on 14 September 1963 against West Bromwich Albion at Old Trafford in a 10 victory. He then dropped back into the reserves, before scoring his first goal for the first team in his second appearance in a 51 win over Burnley on 28 December. Manager Matt Busby then kept Best in the team, and by the end of the 196364 season, he had made 26 appearances, scoring six goals. Manchester United finished second, four points behind Liverpool. They also reached the semi-finals of the FA Cup, where a defeat to West Ham United cost Best the chance to break a record; in 