Having guided Donegal to 2010 All-Ireland Under 21 Football Championship final, McGuinness was appointed manager of the senior county team later that year.
[note 1] He began working with the Scottish association football club Celtic as a coach in 2012, progressing to the position of assistant manager its under-20 squad.
Having previously achieved his UEFA Pro Licence, he was the first person to be appointed as an inter-county Gaelic games manager while holding such a qualification.
[7] In early 1992, he sufficiently impressed senior county manager Brian McEniff in a trial game in Ballyshannon to earn a call-up to the squad.
[15] After Donegal lost the final of the 1998 Ulster Senior Football Championship, Jim McGuinness — aged 25 at this time — decided to go to New York for the summer.
[6] McGuinness scored a goal against Armagh ten minutes from the end of the 2002 Ulster Senior Football Championship final.
[16] He started the first game of Brian McEniff's last spell as Donegal manager, a league defeat to Galway in Tuam in February 2003, during which he scored a point.
[20] The story goes[clarification needed] that one day McGuinness tore his cruciate ligaments, broke a leg and smashed a kneecap in a game against Killybegs, leading to months spent languishing at home in self-pity and lethargy.
6/1 outsiders ahead of the match, Naomh Conaill defeated a heavily fancied St Eunan's after a replay to take their first ever Donegal Senior Football Championship.
[23] McGuinness was turned down several times by the Donegal County Board, on one occasion being thwarted by the lack of a plug socket for the projector needed for his PowerPoint display.
In July 2010, McGuinness, having led Donegal to the 2010 All-Ireland U-21 Football Championship final, was appointed as manager of the senior team when his colleague John Joe Doherty resigned in the wake of a disastrous season.
[20] He outlined his intentions: to be in the 2014 All-Ireland Senior Football Championship final after four years of hard labour akin to an Olympiad.
[31] McGuinness's first year as manager proved successful, as Donegal gained promotion to Division 1 after defeating Laois by a scoreline of 2–11 to 0–16.
However, TV pundit Pat Spillane also claimed Bradley was "the best of a bad bunch" and didn't deserve the award at all, causing McGuinness to react furiously.
Donegal edged out Kildare by a scoreline of 1–12 to 0–14, with late points scored by captain Michael Murphy and two veterans, Christy Toye and Kevin Cassidy.
[43] In what went down as a "surreal moment for the viewer", Mícheál Ó Domhnaill famously interviewed McGuinness following a live 2012 league game on TG4 while Cassidy, in the role of television analyst, stood beside him with his head bowed.
[49] McGuinness then led his team to the 2012 All-Ireland SFC final, with a comprehensive semi-final defeat of title-favourites Cork at Croke Park.
In September 2013, McGuinness confirmed he would be staying on for the 2014 season, but that Rory Gallagher, Maxi Curran and Francie Friel had stepped down from his backroom team.
[74] He won 83.33 per cent of his SFC matches during his first spell as Donegal manager (20 wins from 24 games); this included defeats, over a four-year period, of Armagh, Cavan, Cork, Derry, Dublin, Down, Kildare, Kerry, Mayo, Monaghan and Tyrone.
[78] He assisted his club Naomh Conaill with their defensive system during the 2022 Donegal Senior Football Championship, working with the team between the semi-final and final.
[79] On 20 August, Donegal GAA brought forward its monthly county board meeting to the following evening, where the only thng on the agenda was about appointing the new manager.
[80] Finally, on the evening of Monday the 21st of August, the return of McGuinness was confirmed in sensational fashion at that meeting, year one of three (with an option of a fourth) beginning pronto.
In 2014, Sky Sports secured a three-year deal to broadcast live matches from the All-Ireland Senior Football and Hurling Championships.
[6][7] McGuinness's image has been represented on a mural outside Glenties,[84] and a statue bearing the epigraph "Jim the Redeemer" was erected at Laghy close to Lough Derg.
[citation needed] McGuinness successfully applied to the Football Association of Ireland (FAI) to study for a UEFA Pro Licence in 2019, his classmates including Damien Duff and Robbie Keane.
[88] By 2020, he still had not obtained the licence, as two blocks coincided with games in which he was manager but expressed his intention to complete it later in the year (subject to the COVID-19 pandemic restrictions).
[87] Desmond invited McGuinness to several UEFA Champions League games played by the Scottish association football club Celtic, in Glasgow.
[94] It was expected that he would remain as the Donegal manager, spending three days each week in Scotland focusing on the soccer club's academy structure at their Lennoxtown training centre.
[99] In December 2018, McGuinness was named as the new head coach of Charlotte Independence in the USL Championship, where he signed a three-year contract.
[102] McGuinness also secured the loan signings of defender Andrew Gutman and Scotland national team midfielder Mark Hill, in February and March 2019 respectively.