[3] Kearney joined the Sarsfields club at a young age and played in all grades at juvenile and underage levels, enjoying championship success as captain of the minor team in 2007.
[9] Sarsfields failed to retain the title in 2012 after suffering a two-point defeat by Midleton, however, Kearney played in his sixth final in seven seasons on 12 October 2014.
[12][13] Kearney made his senior debut for Cork on 24 June 2012, replacing Darren Sweetnam in the 50th minute of a Munster Championship quarter-final defeat by Tipperary at Páirc Uí Chaoimh.
Three second-half goals through Conor Lehane, Anthony Nash and Pa Cronin, and a tenth point of the game from Patrick Horgan gave Cork a one-point lead as injury time came to an end.
Clare's Shane O'Donnell was a late addition to the team, and went on to score a hat-trick of goals in the first nineteen minutes of the game.
Patrick Horgan top scored for Cork, however, further goals from Conor McGrath and Darach Honan secured a 5-16 to 3-16 victory for Clare.
[19] After taking some time out to recuperate from an injury at the start of the 2017 season, Kearney subsequently returned to the panel for the National League.