Having born in Stockport, Keane had started playing football for South Manchester at an early age. Afterwards, in 2009, he joined academy of prominent club Manchester United. Staying with the youth ranks of the club for two straight seasons, he got promoted to the senior team signing contract on his on 11 January 2011.
Apart from United's youth team, Keane has also represented Ireland at U-17 and U-19 levels as well as England at U-19, U-20 and U-21 levels.
Keane made his senior team debut on 25 October 2011 in a match of EFL Cup against Aldershot Town. Coming on as a replacement in the 70th minute of the game, he helped his team to grab the victory against the latter. However, he was not named in the squad again until 28 January 2012, when he was named on the bench against arch-rival Liverpool in a game of FA Cup.
After achieving well enough playing with the Ireland and England in youth football, Keane received his maiden International call up on 4 October 2016, he was called up for 2018 FIFA World Cup qualifiers. Though, his debut came on little later on 22 March 2017. Playing his first international game, he had come as a starter in a 1-0 friendly defeat against Germany.
Rise to glory
However, Keane didn't get much chances to represent United at senior level but he did represent Manchester United U-23 team in 46 games getting 7 goals and 3 assists in his name. As a result, Leicester City signed him for a short term contract. Keane played his first game for Leicester City on 6 November 2012 against Bolton Wanderers.
On 12 February, he scored his first goal in a 2-1 defeat against Huddersfield Town at FA Cup. Little later, on 5 March, he netted an equaliser in the 90th minute against Leeds United getting a point for his team.
After staying with couple of different clubs for few years on loan, he made his full time transfer to Burnley in January 2015. He started the Championship season on a positive note scoring twice in the first month and finishing the season with 5 goals. On 26 September 2016, Keane netted his first goal in Premier League against Watford.
He remained a key player throughout and after the season, consequently on 17 April 2017 he was also named as one of the six players shortlisted for the PFA Young Player of the Year award.
Apart from Manchester United, Leicester City and Burnley, Keane has also played with other clubs such as Derby County, Everton FC and Blackburn Rovers.
On 3 July 2017, he joined his current club Everton and made his debut for the club in a 1-0 win against Stoke City on 12 August 2017. Few days later, on 17 August, he scored his first goal for Everton against Hajduk Split in a play-off round first leg of UEFA Europa League.
Kean played most of his games for Burnley FC, 108 of them scoring 7 times. Most of his goals have come in Championship, 10 of them in 86 games. Overall, he has played 240 games in various leagues including Premier League and Reserve League scoring 21 goals and providing 9 assists.
In international football, he has got 4 appearances for England.