Liam David Ian Cooper (born 30 August 1991) is a professional footballer who plays as a centre-back for Bulgarian First League club CSKA Sofia and the Scotland national team.

[12][13] He briefly returned to the first team under Nick Barmby to form a solid partnership with James Chester in March 2012 for the rest of the season following an injury to Jack Hobbs.

The club reached the 2014 Football League Trophy Final and played at Wembley Stadium, but ultimately lost 3–1 to Peterborough United in front of more than 35,000 fans.

After weeks of negotiations, Leeds agreed a deal for £600,000 plus add-ons relating to appearances, a future sale and promotion; with Cooper joining the club on 13 August.

He would struggle for consistency under a succession of managers, losing his starting place to Sol Bamba and later to Pontus Jansson, but would still go on to make over 100 appearances during his first four seasons with the club.

[21] His propensity to be a liability in games earned him the disparaging nickname 'League One Liam' among Leeds fans at the time, but Cooper remained a highly respected captain amongst his teammates.

In Bielsa's first game, he scored the third goal in a comprehensive 3–1 victory over promotion favourites Stoke City, as Leeds ascended to the top of the Championship by Christmas.

[29] With questions again being asked of Leeds' ability to maintain the form over the course of a full season, Cooper would score a crucial equaliser in a 1–1 draw in the following game against promotion rivals Brentford.

[31] The result proved to be a catalyst for the Yorkshire club's season, as they went on to win their next five games with Cooper being part of a defence that would also keep five clean sheets, taking the team back to the summit of the table and reestablishing a seven–point lead in the automatic promotion places.

[33] The season would resume behind closed doors three months later in June, with Leeds' five match winning run coming to an immediate end with a 2–0 defeat to Cardiff City.

[37] Cooper joins a select group of just 70 players[38] that have made over 200 appearances for the club, including current teammate Stuart Dallas who also hit the milestone later in that season.

[42] Cooper received his first call-up to the senior Scotland squad on 10 March 2016 for a friendly against Denmark,[43] but he would have to wait for more than three years to make his debut in a 2–1 defeat to Russia on 6 September 2019.