was an English footballer who won every domestic honour in the game with Arsenal and Liverpool in the 1970s and early 1980s. Kennedy played as a forward for Arsenal and then played as a left-sided midfielder for Liverpool. He scored 148 goals in 581 league and cup appearances in a 15-year career in the English Football League. Also, he won 17 caps for England between 1976 and 1980, scoring three international goals.

Kennedy turned professional for Arsenal in November 1968. He made his first-team debut 10 months later and went on to win the Inter-Cities Fairs Cup in 1970, the First Division and FA Cup Double in 1970–71, and then play on the losing side in the 1972 FA Cup final. His form then declined, and he was sold to Liverpool for a club record £200,000 fee in July 1974, at the same time that Bill Shankly resigned as manager. He initially struggled at the club, but after manager Bob Paisley converted him to a left-sided midfielder, he went on to help Liverpool become the dominant club in English football from 1975 to 1982. During his time at the club Liverpool won the First Division five times (1975–76, 1976–77, 1978–79, 1979–80, and 1981–82), the FA Charity Shield four times (1976, 1977, 1979 and 1980), the European Cup three times, (1977, 1978, and 1981), and the UEFA Cup (1976), UEFA Super Cup (1977), and League Cup (1981). He also picked up runners-up medals in the FA Cup (1977), UEFA Super Cup (1978), League Cup (1978), and World Club Championship (1981) and won the Match of the Day's Goal of the Season award in 1978–79.

He was a strong player with an excellent first touch, intelligence, and all-round ability. This allowed him to transition from a forward to a midfielder at Liverpool. Despite his trophy successes with Arsenal and Liverpool, after winning six caps for the England under-23 side, he could not translate his club form into a good international career. He was used as a stand-in for Trevor Brooking before he retired from international football in frustration in March 1981. His only international tournament appearance was at Euro 1980. Bob Paisley described him as \"one of Liverpool's greatest players and probably the most underrated\".

Kennedy joined Swansea City for a £160,000 fee in January 1982 and added a Welsh Cup winners medal to his collection four months later. However, the effects of Parkinson's disease began to reduce his effectiveness on the pitch, and he dropped into the Fourth Division with Hartlepool United in November 1983. During the 1984–85 season, he spent a brief time as player-manager of Cyprus club Pezoporikos and later played for Northern League club Ashington. He was diagnosed with Parkinson's disease in November 1984. His life after football was difficult, as he had to deal with the effects of Parkinson's, the loss of his business, and the breakdown of his 15-year marriage. He remained reliant on charity to fund his medical expenses and was forced to sell his medal collection and caps in 1993.