Celtic

In October 1961, Gemmell joined Celtic from Coltness United;^[2] he signed youth terms on the same day as right winger Jimmy Johnstone, who lived a few miles away and would also have a long association with the club.^[3] He was one of the 'Lisbon Lions' who won the 1967 European Cup final against Inter Milan, a final in which Gemmell scored an equalising goal with a shot from outside the penalty area.^[4] Ironically, Gemmell should not have been in position to score the goal, as he had ignored team orders for one full-back to stay in defence at all times; the right back Jim Craig had already ventured forward, and it was he who played the square ball for Gemmell to shoot, with both advancing on the Inter box.^[3] With this triumph, Celtic also sealed the first European Treble and the only Quadruple to date.^[5][6] Gemmell was one of just two Lisbon Lions to appear in all 59 matches in major competitions, the other being John Clark.^[7] Gemmell also scored in the 1970 European Cup final in a defeat to Feyenoord,^[8][9] making him currently one of only three British footballers to score in two different European Cup finals, the others being Phil Neal of Liverpool and Gareth Bale of Real Madrid.^[10][11]

Gemmell made 418 appearances for Celtic and scored 63 goals.^[12] This total comprised 247 league (37 goals),^[11] 43 cup (5 goals), 74 league cup (10 goals) and 54 European (12 goals) appearances. His record for penalties was 34 goals from 37 attempts.^[13] He placed sixth for the Ballon d'Or in 1967 and 24th in 1968.^[14][15]

In his book, Lion Heart, Gemmell revealed that, during his time at Celtic, he was on the receiving end of sectarian abuse from certain teammates; he and teammate Ian Young had been the target of "a handful" of colleagues who had wanted an all-Catholic team.^[3] He also stated that he received verbal abuse on several occasions from some supporters of Old Firm rivals Rangers due to his perceived status as a 'turncoat' (as a Protestant who played for Celtic), such as when attending matches many years after retiring.^[3]

Later career

In December 1971, Gemmell transferred to Nottingham Forest to cover for Liam O'Kane. At the end of that season Forest were relegated from the top flight.^[16]

In 1973 he had a short stint with the Miami Toros in the North American Soccer League. He returned to Scotland, signing for Dundee in July 1973, and won the 1973 Scottish League Cup final against former team Celtic.^[17] He retired from playing in 1977.^[13]

International

Gemmell made his international debut for Scotland against England at Hampden on 2 April 1966.^[18] The following year on 15 April, he played in the famous Home Championship match where Scotland recorded a 3–2 victory over World Champions England at Wembley Stadium, ending that team's run of nineteen games without defeat.^[19] He won 18 caps and scored one goal from the penalty spot against Cyprus in an 8–0 win in a 1970 World Cup qualifier.^[13][20] Gemmell's final appearance for Scotland came in 1971.^[13]