It’s the first time Northern Ireland are hosting The Open since 1951 and there was plenty of optimism in the week leading up to Thursday for McIlroy’s chances.
The 30-year-old Ulsterman was listed as the favourite heading into the tournament and it looked as though he was striving under the pressure.
That was until his very first tee shot on the first hole.
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McIlroy hooked his tee shot left into the deep stuff, which struck 34-year-old Anna McKelvey in the stomach and breaking her phone in the process.
Things only went from bad to worse on the first hole as he dropped out of bounds before hitting his third shot left again into the heavy rough where he took an unplayable lie.
Eventually he found the bottom of the cup for a quadruple bogey and quickly moved to five-over par at the third after his tee shot bounced off the green.
McIlroy seemed to compose himself on the ensuing holes, even pulling two back on the seventh and ninth.
At three-over par, McIlroy would have likely been content with taking that score into Friday.
But then disaster struck once again at the 16th hole as he took a miserable three putts from just five feet for a double bogey.