Crossmaglen Rangers (1)

In 1993 Kernan became manager of Crossmaglen Rangers. At the time Crossmaglen football was at an all-time low. Three years later in 1996, after the club had won four under-21 county titles in-a-row, Kernan guided the senior side to a first county championship in 11 years. Crossmaglen went on to claim the Ulster club title before defeating Knockmore to win the 1997 All-Ireland club title. In 1997 and 1998 Kernan guided Crossmaglen to two further county titles. The latter win was later converted into a second set of Ulster and All-Ireland titles. In 1999 Cross captured a fourth county title in-a-row as well as a second successive Ulster title. On St. Patricks Day, 2000 Kernan's side went on to win a third All-Ireland title in four years. Following this victory Kernan decided to retire from club management. He would later return in 2013.

Armagh

In 1989 Kernan got a first taste of inter-county management when he served as assistant to the Armagh manager, Paddy Moriarty. After Armagh were beaten by the eventual Ulster champions in 1989, 1990 and 1991 Moriarty decided to resign as manager and Kernan also walked away.

In November 2001, Kernan was appointed manager of the Armagh senior football team. ^[3] No stone was left unturned in preparing the team.

Eight months later Kernan's side later went on to win the 2002 Ulster title. This win allowed them to advance to an All-Ireland quarter-final meeting with Sligo; however, no Armagh team had won a championship game in Croke Park in twenty-five years. Kernan's side defeated Sligo after a replay before disposing of Dublin in the All-Ireland semi-final. At half-time during that match Kernan pulled the first of two famous stunts designed to inspire the team. He produced the old Armagh jersey that he wore in the 1977 All-Ireland final, and told his players that this would be their reward.

In the subsequent 2002 All-Ireland final, Kerry were leading Armagh at the interval. During his half-time speech he pulled the second of those famous stunts when he produced his runners-up plaque from the 1977 All-Ireland final and smashed it in the dressing room. Armagh later went on to defeat Kerry by a single point to win their first All-Ireland title ever.

In the 2003 Championship Armagh reached the All-Ireland final once again, however this time they were beaten by Tyrone.

Kernan's Armagh side recaptured the Ulster Senior Football Championship in 2004 against Donegal in the first ever Ulster final to be held at Croke Park.

In 2005 he guided the county to their first ever National League title, before successfully defending the Ulster Championship against Tyrone. The following year Armagh became the first team since the 1959–1961 Down side to win the Ulster Championship three years in a row. ^[3]

In Kernan's five seasons in charge, Armagh played 36 Championship games and lost just seven of them, winning 23 and drawing six. ^[3] The side never lost a Championship replay under him. ^[3]

His record as manager of Armagh is unequalled and he has confirmed his status as a legend as both a player and manager.

Ulster

In August 2008, Kernan was announced the new manager of Ulster for the Railway Cup campaign. ^[4] He replaced Donegal man Brian McEniff who had held the role since 1982. ^[4]

Galway

In September 2009, Kernan was announced as the new manager of the Galway senior football team. ^[5] However, in August 2010, he resigned after a very unsuccessful year with the result of Galway getting knocked out of the championship early by being defeated by Wexford.

Crossmaglen Rangers (2)

On 27 March 2013, Kernan was reappointed manager of Crossmaglen Rangers. ^{[6] [7]}

Ireland

In late March 2015, Kernan was appointed manager of the Ireland international rules football team for the 2015 Series against Australia. ^[8]