Liverpool-born Flanagan became one of the youngest players in Liverpool’s history to be allocated a first-team squad number when he was given the No. 38 shirt for the 2010/11 season when still several weeks short of his eighteenth birthday. Like his fellow defender Jack Robinson, Flanagan had impressed in Rodolfo Borrell’s Under-18 team at the Academy. Tony Barrett, who was then at the Liverpool Echo, predicted big things for the young Liverpudlian as the step-up to the reserves did not phase Flanagan in the slightest and he “just got on with the job in hand with the minimum of fuss, defending with a characteristic zeal but never missing the chance to get forward and get crosses into the box whenever the opportunity presented itself.”

Flanagan made the sort of impact on his first-team debut that all young players must dream about. The right-back played from the start against Manchester City at Anfield in April 2011 with great confidence and maturity, as he did only six days later in an equally tough encounter with Arsenal in London. At the Emirates, he accidentally knocked out his captain, Jamie Carragher, but did not let that affect the level of his performance. He then played the full 90 minutes against Birmingham followed by 80 minutes against Newcastle. At Fulham in early-May, he was asked to play on the left so that Glen Johnson could be accommodated on the right. Despite being in a position that he was not accustomed to, he still played with great assurance. To play so well in the final seven Premier League matches of the season was very commendable and it is hard to believe that he only became eighteen in January 2011.