signed professional forms with the club in November 1968. He had a difficult task though to win a first-team place, as manager Bertie Mee used only 15 players throughout the entire 1968–69 season, during which time Kennedy made 20 appearances for the Reserve team as they claimed the Football Combination Division One title. He made his first-team debut on 29 September 1969, against Glentoran in the Inter-Cities Fairs Cup and his First Division debut as a substitute on 18 October, a 1–1 draw with Sunderland at Roker Park. He scored his first goal for the Gunners in the reverse fixture against Sunderland at Highbury, which ended in a 3–1 win. He went on to appear as a 77th-minute substitute in the first leg of the Inter-Cities Fairs Cup final against Belgian club Anderlecht at Constant Vanden Stock Stadium, and scored a late goal in a 3–1 defeat. Though he did not appear in the second leg, his goal proved to be decisive as Arsenal claimed a 4–3 aggregate victory to win the first European trophy in the club's history. Charlie George broke his ankle on the opening game of the 1970–71 season, and Kennedy replaced him as John Radford's strike partner for the following game, and went on to feature in the remaining league fixtures of the campaign as Arsenal went on to be crowned champions. They exited the Inter-Cities Fairs Cup with defeat to German side 1. FC Köln at the quarter-final stage, though after their draw with Lazio in the First Round Kennedy was attacked by some of the Lazio players in an Italian restaurant, and in the ensuing brawl police pulled a gun on teammate Eddie Kelly; Kennedy later said he was targeted by the Lazio players due to his "cheeky face". Back in the league, he scored his first hat-trick in victory over Nottingham Forest, though he admitted after the match that he was "still expecting to be dropped any minute". Arsenal overtook Leeds United to win the league title on the final day of the season, Kennedy scoring the only goal of the game with a late header in a 1–0 victory over North London derby rivals Tottenham Hotspur at White Hart Lane. In the FA Cup, Arsenal progressed past Yeovil Town, Portsmouth (following a replay), Manchester City, Leicester City (following a replay), and Stoke City (following a replay), before meeting Liverpool in the final