Saidy Janko

Celtic On 1 July 2015, Celtic announced that they had signed Janko on a four-year contract. He made his debut nine days later, coming on as a substitute for Gary Mackay-Steven 75 minutes into Celtic's 1–0 win over Real Sociedad in a pre-season friendly at St. Mirren Park. Janko made his competitive debut on 1 August, coming on as a second-half substitute during Celtic's 2–0 win over Ross County in the opening league match of the Scottish Premiership season.

On 31 August 2016, Janko joined Championship club Barnsley on a one-year loan deal. He scored on his debut in a 4–0 away win against Wolverhampton Wanderers on 13 September.

Saint-Étienne On 7 July 2017, Janko left Celtic for French Ligue 1 club Saint-Étienne, signing a four-year contract.

Porto Janko moved to Portuguese club Porto on a five-year contract on 17 June 2018. He returned to the EFL Championship on 31 August that year, joining Nottingham Forest on loan for the 2018–19 season.

On 1 July 2019, Janko entered football in his native country for the first time in his career, being loaned to Young Boys for the Swiss Super League season. He scored his first goal on 14 September in the second round of the Swiss Cup, in an 11–2 win against fifth-tier FC Freienbach. In total, Janko played 46 official matches, starting 38 of them, as they won the double (Super League and Cup). He made his debut in La Liga 24 days later in a 2–0 home loss to Alavés.

On 27 June 2022, VfL Bochum announced the signing of Janko on a season-long loan, with an option to buy at the end of the spell.

Young Boys On 30 June 2023, Real Valladolid announced that Janko had joined Swiss side Young Boys, where he had previously played on loan while a Porto player, on a permanent basis.

He missed out on the chance to face his former club, Celtic, in the Champions League in January 2025, due to injury.

International career Janko was born in Zürich to a Gambian father and an Italian mother. He was a youth international for Switzerland from 2012 to 2015, before opting to represent the Gambia in 2021. He made his debut for the Gambia national team in a 2–0 friendly loss to Sierra Leone on 9 October 2021.

He played in the 2021 Africa Cup of Nations, his national team's first continental tournament, where they reached the quarter-finals.

Personal life He is the brother of fellow professional footballer Lenny Janko.

International

Honours Celtic Scottish Premiership: 2015–16, 2016–17

Young Boys Swiss Super League: 2019–20 Swiss Cup: 2019–20

Individual Denzil Haroun Reserve Player of the Year: 2013–14