2013/14 English Premier League
Allen was part of the Swansea City youth set-up from the age of nine, until he followed manager Brendan Rodgers to Liverpool in the summer of 2012.
The midfielder was highly rated from an early age and then-manager Kenny Jackett gave Allen his debut in the FAW Premier Cup away tie to local Welsh Premier League side Port Talbot Town when he was only 16.
He signed his first professional contract soon afterwards but his career was hindered by a bad ankle ligament injury and he left for a month's loan to join Wrexham.
Upon his return, he blossomed into an important player for the club and under Roberto Martinez, and then Rodgers, he became one of the key components of their short-passing style. Lauded for his accuracy and skill in 2011-12, he followed Rodgers to Anfield when the club paid his £15 million release clause.
Strengths: Incredibly accurate with his passing, he has a good eye for his team-mates' positions and ties the play together with his vision and intelligence.
Weaknesses: Not the most creative player or the best tackler, his game is a little limited.
Career high: After a season in which he rivalled the great Xavi in the passing stakes, he moved to Liverpool for £15 million in 2012.
Career low: Sent on loan to Wrexham in 2008, he must have wondered if he had a future at the club.
Style: Technical, metronomic, accurate, a fine passer of the ball.
Quote: "He's five foot six but, in terms of a footballer, he is seven foot six. He is absolutely immense - his courage to get on the ball; his body work is fantastic; how he reads the game; his football intelligence. This kid will play at the top and is playing at the top." Brendan Rodgers on his new signing, September 2012
Trivia: In 2011-12, he made 2,177 passes in the Premier League - the average number made by a midfielder was just 1,321.
BARCLAYS PREMIER LEAGUE