Kieran Tierney (born 5 June 1997) is a Scottish professional footballer who plays as a left-back for Premier League club Arsenal and the Scotland national team.

He has spoken of his hope of emulating the late Tommy Gemmell, a member of the Lisbon Lions team who also grew up in Wishaw (specifically, Craigneuk) and played in the same position.

[6] Tierney progressed through the various youth ranks and earned a reputation as a dependable wide player in the club's development squad, both in defence and attack.

[11][12] Tierney made his competitive senior debut for Celtic on 22 April 2015, coming on as an 81st-minute substitute in a Scottish Premiership match against Dundee.

[14] Tierney enjoyed a breakthrough season in 2015–16, appearing in over 30 matches and displacing the more experienced Emilio Izaguirre as first-choice left back.

[18] After making his first appearances in the group stage of the UEFA Champions League, Tierney suffered ankle ligament damage during training on 27 October 2016 and was initially ruled out of action for two months.

[19] During the layoff, which caused him to miss the League Cup Final, he received treatment on a recurring shoulder injury and attended several Celtic matches as a typical supporter in the company of his childhood friends.

[20] On 22 January 2017, after missing three months, he made his long-awaited return to the Celtic team in a Scottish Cup tie against Albion Rovers.

[39] On 28 August 2020, Tierney was in the starting 11 in the 2020 FA Community Shield, which Arsenal clinched a 5–4 victory over Liverpool in the penalty shootout after the match was 1–1 after 90 minutes.

[45] Arsenal signed Oleksandr Zinchenko from Manchester City during the summer of 2022, and during the 2022–23 season the Ukrainian played most Premier League minutes at left back ahead of Tierney.

[54] Tierney played for the first half of the match, which Scotland won 1–0 at Hampden Park; he was replaced at the break by his Celtic teammate Charlie Mulgrew.

[55] Due to his greater versatility compared to fellow left-back Andrew Robertson,[56] Tierney was deployed at right back in Scotland's matches against Slovenia,[57] Lithuania and Slovakia, and on the left of a three-man defence in the fixture at home to England during World Cup qualifiers in 2017.

[61] In November 2019, Tierney withdrew from the Scotland squad ahead of their UEFA Euro 2020 qualifiers against Cyprus and Kazakhstan due to a hip injury.

[62] In October 2020, he was required to pull out of the squad for a Euro 2020 play-off semi-final against Israel after being in close contact with Stuart Armstrong, who had tested positive for COVID-19.

[citation needed] Tierney appeared five times for Scotland during their successful UEFA Euro 2024 qualifying campaign, with the team winning all five of the matches he played and conceding only one goal.

[68] A week later, he started the opening match of the tournament, playing 76 minutes before being substituted for Scott McKenna, as Scotland lost 5–1 to hosts Germany.