Shelbourne 1 Celtic 4
Shelbourne became Celtic’s first victims of the season as ths Scottish champions pushed the uncertainty over manager Martin O'Neill's future to the back of their minds by winning their first pre-season game in style.
Man of the match John Hartson claimed a brace, while Didier Agathe and Chris Sutton both grabbed a goal apiece against the eircom League Premier Division champions.
Shels tried to fight back and they managed to find the back of the net through Stephen Geoghegan to cancel out Hartson's opener, but O’Neill’s men ultimately proved to be too strong.
This game was billed as the meeting of the Irish and Scottish champions but it was clear to see that O'Neill was the star attraction. His emergence from the Tolka Park tunnel provoked a frenzy of activity from the assembled photographers and TV cameramen as chants of 'Martin O'Neill, Martin O'Neill' rang around the park from both sets of fans.
Despite the intense speculation which has linked him with the vacant Leeds United job, O'Neill has already assured Irish supporters that he will remain at Parkhead for the remainder of his contract - and his players did not seem overly concerned as they kicked off their first pre-season friendly.
Shelbourne had already tasted their first league defeat last night, going down 3-0 to Cork City at Turners Cross last night before but Celtic showed no signs of slipping from the standards they set last season.
The Parkhead side were without Swedish stars Henrik Larsson and Johan Mjallby - who had both been given time off to recover from their World Cup exploits - and injured duo Neil Lennon and Joos Valgaeren were also missing.
But that did not prevent Celtic from taking the lead just six minutes into this game.
Midfielder Liam Miller - the 21-year-old who spent last season on loan with Danish outfit Aarhus - was handed a starting place and he grabbed the opportunity with both hands by providing the cross which was met by Hartson to nod home the opener.
To their credit, Shelbourne fought back and they were on level terms again after 17 minutes when Wes Holihan's inside pass was met by Geoghegan who fired past Hoops goalkeeper Robert Douglas.
But Celtic were looking the more dangerous side and they were back in front nine minutes later.
Young defender Stephen Crainey picked out Hartson with the cross and, once again, the big striker was on target with the header.
The Scottish champions extended their lead four minutes later when Jackie McNamara floated a long ball into the path of Agathe who slid home Celtic's third goal.
The game turned sour shortly before the half-time break when Alan Thompson and Stewart Byrne confronted each other and both found their names in the referee's book.
As is typical with most friendlies, there were a large number of substitutions and O'Neill made no less than eight changes during the interval.
Only Miller, McNamara and Crainey remained from the side who played the opening 45 minutes and Celtic's only new signing, David Fernandez, was given his chance.
The former Livingston striker tried to set up Sutton after 52 minutes but his shot was easily held the Shelbourne goalkeeper and Fernandez's contributions to the game were limited after that.
Sutton did manage to add his name to the scoresheet two minutes later but this time the provider was Colin Healy and the former Chelsea hitman left Williams helpless when he nodded home the Hoops' fourth goal.
Sutton was unlucky not to grab a second goal as the game entered the last 10 minutes when he was denied by a superb point-blank save from the Shelbourne goalkeeper.