He was scouted playing for a local based club, and was recommended to Alhaji Sly Tetteh, former CEO of Liberty Professionals.

[14][15] He made his debut on 11 August 2012 against Napoli in the 2012 Supercoppa Italiana, scoring a goal as Juventus went on to win 4–2 after extra time.

[16] Due to his impressive performance against Napoli, Antonio Conte, who was Juventus's coach at the time, decided to start him in the opening league match of the 2012–13 season, against Parma, on 25 August: he made an immediate impact, by setting up Stephan Lichtsteiner's goal in a 2–0 home win.

[20] On 9 March 2014, Asamoah scored a notable goal in a 1–0 home victory over Fiorentina,[21] as Juventus went on to defend the Serie A title and the Supercoppa Italiana that season.

[27][28] On 25 September 2016, it was confirmed that Asamoah would be sidelined for six weeks after limping off the pitch a day before away to Palermo with a sprained right knee; tests at the J-Medical centre revealed he suffered the complete tear of the medial meniscus ligament.

[39] On the international level, Asamoah was given his debut for the Ghana national team, Black Stars, in 2009, under French manager Claude Le Roy.

[40][41] A dynamic, hardworking, energetic, versatile and tactically intelligent player, Asamoah was primarily known for his pace, strength, stamina, and his outstanding technical characteristics, as well as his ability to read the game; although he primarily served as a ball-winner, these attributes allowed him to be effective both offensively and defensively, and enabled him to play in several positions along the pitch in defence or midfield.

A predominantly left-footed player, with Juventus, Asamoah was usually deployed as a full back, wing-back, or wide-midfielder on the left flank, although he had previously also been used in the centre as a defensive, central, box-to-box, or offensive midfielder prior to joining the club, and even in the "mezzala" role.

In addition to his physical and athletic attributes, he was a very agile footballer, with good vision and an ability to make attacking runs and get into good offensive positions from which he could create chances for teammates with throughballs or deliveries into the area from the wing; he was also a neat passer, a powerful striker of the ball from distance, and a skilful dribbler.