The Los Angeles Galaxy hitman bagged a 17-minute treble to help the Boys in Green into a 3-0 half-time lead over the minnows in Dublin tonight.
Below, Sports Mole offers an in-depth analysis of the seven-goal rout at the Aviva Stadium.
On target: 23
On target: 1
Was the result fair?
Stats occasionally lie. Not this time. It was men against boys, pros against amateurs from the very first minute this evening. It is entirely possible and probable that nobody inside the Aviva Stadium will ever see a more one-sided game of football in a 'competitive' outing. But was it fair? No. It could, and probably should, have been a rout that reached double figures.
Republic of Ireland's performance
It was billed as a training match ahead of Tuesday's Euro 2016 qualifier away to Germany, and it never looked like anything less for Ireland, who were seven goals to the good after the 56-minute mark. It was a ruthless showing from Martin O'Neill's side, a performance with plenty of flair to match the grit that they showed to beat Georgia last month.
Nobody from an Irish perspective will read too much into it by virtue of Gibraltar's calibre, but it will still provide the Boys in Green with a timely morale boost ahead of what is surely the most daunting fixture of Group D.
Gibraltar's mere presence in this Euro 2016 qualification campaign shows how far they have come as a footballing nation, having only earned UEFA membership roughly 18 months ago. However, results like these and the ones that follow - and they will - illustrate just how far away they are from truly competing. With just three professionals in their ranks, results like this are inevitable. It is their first ever qualifying campaign and, with 14 goals conceded in two outings, it is not looking good for them. Welcome to competitive football, lads.
Sports Mole's man of the match
Wes Hoolahan: Keane was the obvious choice by virtue of his 17-minute hat-trick, but Hoolahan was instrumental in all three of those goals and ultimately proved more deserving of the man-of-the-match award.
First, he played a sublime outside-of-the-boot ball to find McGeady in the build-up to Keane's opener, before threading the veteran striker through for his second not long after. Hoolahan then won the penalty which allowed Keane to bag his hat-trick, and then got on the scoresheet himself in a ruthless second-half showing. Keane will get the plaudits - and rightly so - but Hoolahan's contribution tonight cannot be ignored. It was no surprise that Ireland did not score again after he left the field.
It is no exaggeration to claim that all seven of Ireland's goals could be put down as 'gaffes' from Gibraltar goalkeeper Jordan Perez - including his own goal. However, the one that Perez - a full-time fireman, in his defence - deserves most condemnation for would be the third, where he conceded a soft penalty and was then punished by Keane from the spot. It would be a major surprise to see him recalled for their next outing.
Cypriot referee Leontios Trattou had a quiet game and was afforded the luxury of keeping his cards tucked away in his pocket for the duration of the match.
Republic of Ireland: O'Neill's side now turn their attention toward a clash with world champions Germany in Gelsenkirchen on Tuesday.
Gibraltar: Gibraltar are also back in action on the 14th as they host Temuri Ketsbaia's Georgia side.