THE world now knows that Rory sleeps with his mouth open, thanks to girlfriend Caroline Wozniacki.
The tennis star shared the photo of her boyfriend in a deep sleep with his mouth wide open with her 550,000 Twitter followers captioned: "Jetlag @mcilroyrory ? Lol!!"
Many responded to the tweet warning Caroline that Rory was unlikely to be best pleased with her for sharing the photo.
It appears Rory may have been suffering side effects from the compressed air pressure on a flight the day before, as sleeping with your mouth open is a sign of nasal congestion.
Caroline is not the first celebrity to share a photo of a partner from their bed.
Russell Brand famously tweeted a pic of then wife Katy Perry first thing in the morning, but he quickly deleted it when she was made aware of what he had done.
24-year-old Rory has been catching up on his Zs this week at Dublin's Westbury Hotel, where he is believed to be staying with a bunch of pals.
The Co Down golfer was in flying form when he visited the plush hotel with five friends following a recreational round of golf.
The visit is the second in the past week for McIlroy to the capital. He was said to have partied at 37 Dawson Street last weekend with his pals.
He is believed to have been introduced to model Nadia Forde, who recently launched her singing career at a Republic of Ireland game at the Aviva stadium.
She was out that night celebrating with Rob White, husband of model boss Andrea Roche, who announced she is expecting the couple's first child.