St. Finbarr's College Kenny first came to prominence as a hurler with
St. Finbarr's College in
Cork. He played in every grade of hurling and collected a
Dean Ryan Cup medal in 1996 before joining the college's senior hurling team. On 7 March 1999, Kenny scored four points from midfield when St. Finbarr's College suffered a 1–14 to 1–08 defeat by
St. Flannan's College from
Ennis in the
Harty Cup final.
University College Cork As a commerce student at
University College Cork, Kenny immediately became involved in
Gaelic games. As a member of the freshers' hurling team in his first year he won an All-Ireland Championship. Kenny joined the senior hurling and
Gaelic football teams during his second year. On 23 February 2002, Kenny was at right wing-forward when UCC suffered a 0–06 to 0–05 defeat by the
Institute of Technology, Sligo in the
Sigerson Cup final. On 6 March 2004, Kenny captained the senior hurling team to the
Fitzgibbon Cup final against the
Waterford Institute of Technology. He lined out at right wing-back in the 0–11 to 0–09 defeat.
Grenagh Kenny plays his local club hurling and Gaelic football with his local club in
Grenagh and has enjoyed much success. He was regarded as a great
dual player at under-age levels and he quickly joined the top team with the club. In 1999 Kenny enjoyed his first major success with Grenagh when he captured a divisional junior hurling championship winners' medal following a 2–11 to 1–11 victory over
Ballinora. This was the beginning of a great decade of success for Grenagh in the Muskerry junior hurling championship. In 2000 Kenny added a second consecutive Mid Cork junior title to his collection as
Aghabullogue were defeated by 2–12 to 1–6. Grenagh completed a divisional 'double' that year as the club's football team beat
Donoughmore by 0–13 to 0–4. In spite of these victories Kenny's side enjoyed little success in the wider county championship. 2001 proved to be another hugely successful year for Kenny and for Grenagh. Defeats of Donoughmore and
Ballingeary gave Grenagh a second consecutive 'double' in the divisional junior championship. After surrendering both their football and hurling titles in 2002 Grenagh bounced back in 2003. A narrow 1–14 to 2–9 win over
Ballincollig gave Kenny a fourth divisional junior championship winners' medal in five years. A fifth divisional junior hurling championship title quickly followed for Kenny in 2004 as Grenagh recorded a thrilling 0–19 to 3–9 victory over
Cloughduv. The club later reached the final of the
county junior championship, with
Ballygarvan providing the opposition. A close game ensued, however, at the full-time whistle Kenny's side were narrowly defeated by 3–7 to 1–12. In 2005 Kenny captured his second three-in-a-row of divisional junior hurling titles. The 2–11 to 1–7 defeat of
Blarney gave him a sixth winners' medal in the championship in seven seasons. 2006 saw Grenagh surrender their divisional hurling title, however, while the club's hurlers failed the footballers enjoyed some success. A 1–10 to 1–6 defeat of
Iveleary gave Kenny a second divisional junior hurling winners' medal. In 2007 the opposite of what happened in 2006 occurred. The Grenagh footballers surrendered their title, however, the club's hurlers reached the divisional final once again. That game against
Dripsey ended in a 1–15 to 2–12 draw. The replay was much more conclusive as Grenagh romped to a 2–14 to 2–7 win. It was Kenny's seventh divisional junior hurling winners' medal. Kenny has also played in the
county senior hurling championship as a member of his local
Muskerry division.
Cork Minor and under-21 Kenny first lined out for
Cork as a member of the minor hurling team during the
1999 Munster Championship. He made his only appearance for the team on 12 May 1999 when he lined out at left wing-back in a 2–16 to 2–12 defeat by
Clare. On 7 July 1999, Kenny made his first appearance for the Cork minor football team. He was selected at left wing-back for the 1–18 to 1–05 defeat of
Limerick. He retained his position on the starting fifteen for the
Munster final on 18 July 1999 and scored a point in the 2–16 to 1–09 defeat of
Kerry. On 18 March 2000, Kenny made his first appearance for the Cork under-21 football team. He lined out at left wing-back in a 1–10 to 0–06 defeat of CLare in the
Munster Championship. Kenny was eligible for the under-21 grade again in
2002. He won a Munster Championship medal as a non-playing substitute on 21 April 2001 following a 1–12 to 0–08 defeat of Limerick in the final. For the third successive season, Kenny was included on the Cork under-21 football team in
2003. He made his last appearance for the team on 9 March 2003 when Cork suffered a 2–09 to 0–14 defeat by Clare.
Junior and intermediate Kenny was drafted onto both Cork junior football team and the Cork intermediate hurling team as a dual player in advance of the respective Munster Championships. He made his only appearance for the Cork intermediate hurling team on 19 June 2001 when he came on as a substitute in the 0–21 to 3–08 defeat of
Waterford. Kenny made his first appearance for the Cork junior football team on 24 June 2001 when he lined out at left wing-back in a 1–13 to 1–07 defeat of Clare. He retained his position on the starting fifteen for the final on 5 July 2001 and ended the game with a winners' medal following a 0–17 to 0–11 defeat of
Tipperary. After missing the subsequent All-Ireland semi-final, Kenny was restored to the left wing-back position for the
All-Ireland final against
Mayo. Kenny collected a winners' medal following the 1–15 to 3–07 victory.
Senior Kenny joined the
Cork senior hurling team prior to the start of the
2002 National League. He made his first appearance for the team on 16 March 2002 when he came on as a substitute for
Fergal Ryan in a 1–24 to 1–12 defeat of
Derry. Kenny was later included on the Cork panel for the
Munster Championship. Kenny became a dual player after being drafted onto the
Cork senior football team at the start of the 2003 season. He made his first appearance for the team on 3 March 2003 when he came on as a substitute for
Mícheál Ó Cróinín at full-forward in a 0–16 to 0–08 defeat of
Dublin in the
National Football League. Kenny made his only
Munster Championship appearance on 11 May 2003 when he lined out at centre-forward in a 0–16 to 0–06 defeat by Limerick. On 8 June 2003, he made his
Munster Championship debut with the Cork senior hurling team when he lined out at right wing-back in a 1–18 to 0–10 defeat of Clare. Kenny won his first
Munster Championship on 29 June 2003 after scoring a point from right wing-back in a 3–16 to 3–12 defeat of
Waterford in the
final. On 14 September 2003, he was again at right wing-back for Cork's 1–14 to 1-11
All-Ireland final defeat by Kilkenny. Kenny ended the season by being nominated for an
All-Star. On 27 June 2004, Kenny scored three points from midfield when Cork suffered a 3–16 to 1–21 defeat by Waterford in the
Munster final. In spite of this defeat, Cork later qualified for the
All-Ireland final against Kilkenny. A 0–17 to 0–09 victory gave Kenny a first
All-Ireland medal. He ended the season by being nominated for a second consecutive All-Star award. Kenny won his second Munster Championship medal on 26 June 2005 after lining out at midfield in a 1–21 to 1–16 defeat of Tipperary in the
final at
Páirc Uí Chaoimh. On 11 September 2005, Cork faced
Galway in the
All-Ireland final for the first time since
1990. Kenny again partnered
Jerry O'Connor at midfield as Cork won the game by 1–21 to 1–16, with Kenny collecting a second consecutive All-Ireland medal. He ended the season by being nominated for a third consecutive All-Star award. On 25 June 2006, Kenny won his third Munster Championship medal after a 2–14 to 1–14 defeat of Tipperary for the second consecutive year in the
final. Cork subsequently qualified for a fourth successive
All-Ireland final, with Kilkenny providing the opposition for the third time. Kenny was at midfield for the 1–16 to 1–13 defeat. He ended the season by being nominated for a fourth successive All-Star award. For the second time in six years, the Cork senior hurling team withdrew their services in sympathy with the Cork senior football team who had also refused to play due to the appointment of
Teddy Holland as team manager and the changing of the rules regarding the selection committee. Because of this, Kenny and his teammates failed to fulfil their opening two fixtures in the
2008 National Hurling League. A third strike at the start of the
2009 National Hurling League saw him and his teammates withdraw from the panel once again before eventually returning. Kenny later said: "People might say they [the strikes] were counterproductive. But I was probably on the higher end of the scale of the experienced players and I still stand by that we were doing what needed to be done...If you feel at the time something is the right thing to do, you have to do it and that’s what we did. I think history will prove long-term that what we did served Cork well." On 2 May 2010, Kenny lined out as midfield partner to
Lorcán McLoughlin when Cork faced Galway in the
National League final. He ended the game on the losing side following a 2–22 to 1–17 defeat. On 11 July 2010, Kenny scored a point from midfield in Cork's 2-15 apiece draw with Waterford in the
Munster final. He was named in the same position for the replay a week later but ended the game on the losing side following the 1–16 to 1–13 defeat. Kenny failed to command a place on the starting fifteen and became a marginal presence during the 2011 season. After Cork exited the championship he contemplated retirement, however, new manager
Jimmy Barry-Murphy convinced him to remain as a role player rather than a first-choice starter. Kenny lined out in his sixth
Munster final on 14 July 2013. He was selected at left corner-back in the 0–24 to 0–15 defeat by Limerick. On 8 September 2013, Kenny came on as a 64th-minute substitute for
William Egan in a 3–16 to 0–25 draw with Clare in the
All-Ireland final. He was again named on the bench for the replay on 28 September 2013, but came on as a 38th-minute substitute for
Daniel Kearney in the 5–16 to 3–16 defeat. Kenny announced his retirement from inter-county hurling on 12 December 2013. He said: "I'm 32 now and I felt it was time to let other lads come through and have their chance. I'm healthy, it's not because of injury, I've had a good innings with Cork, it would have been great to go out with a third All-Ireland medal this year, but it wasn't to be."
Munster Kenny has also lined out with
Munster in the
Railway Cup inter-provincial competition. He played with the province for the only time in 2008, however, Munster were defeated by
Leinster on a 1–15 to 1–12 score line. ==Managerial and coaching career==