But the Laois native is not the boss of the League of Ireland side taking on the Gunners in the Europa League.
He is the club’s opposition analysis scout and as well as a coaching podcast host and manager of Irish amateur side Portlaoise AFC.
But he also just so happens to be the only man at Dundalk with a UEFA Pro Licence.
Dundalk’s actual manager Filippo Giovagnoli and his assistant Giuseppe Rossi don’t have the qualifications to be on the sidelines for a Europa League group game.
It’s just a brief note in the mad world of the recently dethroned champions of Ireland.
A decade ago at the age of 28, Keegan became the youngest Irish person to achieve the UEFA Pro Licence qualification before leading Wexford Youths to promotion to the top tier of Irish football.
“I suppose one way to look at it is the youngest person to get a pro licence in Ireland probably just means I realised I was a s*** player before most people realise they’re s*** players,” said the former Galway United boss.
“I started on the coaching pathway a bit earlier than the rest because I knew I wasn’t going to go too far from an early age.”
Vinny Perth, who had previously succeeded now Irish boss Stephen Kenny in January 2019, was in charge of Dundalk at the start of the season as they began the defence of their fourth title in four years in what has been their most successful period.
Perth, who also didn’t have a UEFA Pro licence, brought in Keegan as opposition scout alongside coaches John Gill and Alan Reynolds who did have the qualifications.
But when they lost out in the early rounds of Champions League qualification, Perth was sacked by the American owners, the investment company PEAK6 who recently sold their stake in Bournemouth. Gill and Reynolds also left.
Then came claims of club chairman Bill Hulsizer, father of PEAK6 founder Matt, was meddling in team selections under Perth.
There was a supposed query if a phone could be placed in the dugout for communication during games. The claims were denied by the Hulsizer family.
But it was even alleged the chairman felt goalkeeper Gary Rogers should take corners owing to his Gaelic football prowess and centre-back Brian Gartland should be on throw-in duties because he is also a basketball coach.
Maybe just an American with little knowledge of the game thinking out loud but there was no denying Giovagnoli and Rossi’s appointment was a shock.
The duo were taken from a junior soccer academy in New York.
Giovagnoli, who played lower league football in Italy in the 1990s, said the job was a “Kamikaze mission” which added further to the confusion.
They may have lost their title in Ireland but Dundalk did manage to reach the group stages of the second-tier continental competition and they have pocketed £4m in prize money already for a club with a turnover of £2m.
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But last week just before their opening Group B defeat by Molde, they were informed that Giovagnoli and Rossi couldn’t be on the sidelines and instead they stood five yards behind the dugout.
“We have to nail down the lines of communication and how to make sure what Filippo needs communicated onto the pitch is got onto the pitch in a timely manner,” said Keegan.
“But it would be ridiculous of me not to say I’m going to enjoy the experience and given I know what Filippo wants I hope and think I can be vocal on the touchline.”
Keegan has spent the last few days doing his main job which is to analyse the Gunners’ weaknesses and strengths to try to cause an almighty upset.
He added: “We are not going just to be tourists in any way shape or form.”