Club Kavanagh won six
Donegal Senior Football Championship (SFC) titles while playing for the St Eunan's club. Kavanagh made a substitute appearance for his club in the
2020 Donegal SFC semi-final loss to Naomh Conaill, and was substituted himself before the end. He also played for
Donegal Boston.
Inter-county Mickey Moran first called Kavanagh into the Donegal senior panel in 2001. Against
Armagh in the 2004
Ulster Senior Football Championship (SFC) final at
Croke Park, he came on as a substitute for the injured
Christy Toye. Against the same opponents at the same venue he played in the 2006 Ulster final, scoring 0–1. Having spent much of the campaign on the bench, he came on as a substitute in the
2007 NFL Final against
Mayo, scoring 0–1. On 19 December 2008, he was named
captain for the 2009 season. Kavanagh went travelling abroad and only returned over
Easter in 2010 but was sprung from the bench directly into the
2010 National Football League game against
Armagh at
O'Donnell Park shortly afterwards, having been sent off in his first game back for St Eunan's. He made his 100th appearance for his county in the
2012 Ulster SFC preliminary round match against
Cavan, and captained the team in the absence of the injured
Michael Murphy. Again against Mayo, this time under the management of
Jim McGuinness, Kavanagh started at midfield in the
2012 All-Ireland Senior Football Championship final. Speaking to
BBC Radio Foyle from his team hotel in Dublin the following morning, he was still hoarse himself and described the win as "surreal". He was nominated to be an All Star in 2012. He won consecutive Ulster SFC titles in
2011 and
2012. Against
Derry in the 2011 Ulster SFC final, he was injured late in the first half and was replaced by
Martin McElhinney. Kavanagh decided to retire from the county set up at the end of 2014. In 2016, he unretired himself and returned to the Donegal panel. In January 2017, Kavanagh finally retired from the inter-county game. It later emerged that much of this apparent indecisiveness was influenced by
Rory Gallagher (McGuinness's assistant and, later, Donegal manager), who would lay in wait at Kavanagh's house, and approach him as he returned home from school, in efforts to attract him (both Rorys also bear a passing resemblance to each other). ==Training regime==