A Glaswegian born in 1994, Robertson was on Celtic's books as a schoolboy but released when he was fifteen. He went on to join Scottish League Two amateurs Queens Park, forcing his way into their first team for the 2012-13 season before being signed by Dundee United. After an impressive season he was named PFA young player of the year in Scotland, having scored three goals from the left-back position.He also made his Scotland debut whilst still a teenager in March 2014, coming on as a second half substitute against Poland in Warsaw.
In the summer of 2014 Robertson joined Hull City where he had an eventful three years. He was twice relegated from the Premier League as well as being promoted from the Championship. He made 99 league appearances, scoring three times and continued to be called up by Scotland, scoring his first international goal against England in a friendly at Celtic Park in November 2014.
Robertson joined Liverpool on 21st July 2017 in a deal reported as being worth as much as £10 million. He expressed a desire to prove he can perform at the highest level and Jurgen Klopp told reporters he believed it was the perfect move for him. He said " For Andrew this is another big step on what has been quite an incredible personal journey in a very short space of time. I know our environment will benefit him and help him push himself even more than he has already. This is a player who does not limit his ambition."
In his first season at Anfield Robertson had to bide his time, but he worked hard in training and took his chances when they came. A strong tackler who chased down every opponent could put in a decent cross, by the end of the campaign he had ousted Alberto Moreno from the left back spot and scored his first goal for the club in the last league game of the season against Brighton. He began 2018-19 as first choice left back and when he joined up with the Scottish international squad at the start of September was announced as the new national captain.
Throughout the season Robertson continued to exceed all expectations. He appeared in 36 of the 38 Premier League games and missed just one in the Champions League, through suspension. Retaining his fitness, the only time he was laid up was when dental surgery ruled him out of a Scottish World Cup qualifier in Kazakhstan. He defended with tenacity, terrorised opposition defenders with his marauding runs down the flank, whipped in crosses and assisted with eleven goals on the home front, a joint Premier League record for a defender. He signed a new and improved contract in January 2019 but remained grounded, tweeting after the Champions League triumph "Just a wee guy from Glasgow living he absolute dream".