Sweeney is hosting a dinner in the Irish reality TV show “Come Dine with Me,” which is to air on TV3.
“My theme is a tennis and golf theme. I chose it tonight because I used to go out with Rory," she said, according to the Irish Independent.
McIlroy is a star golfer and his new girlfriend is former world number one Caroline Wozniacki.
"The tennis thing is obviously a little joke because Caroline is world No 1," she added.
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The Independent reports that one of the guests at the dinner thought Sweeney should concentrate more on how her life is going.
"For a woman who is trying to move on from a previous relationship and rebuild her life and establish her own personality she should stop harping on about golf to be perfectly honest," said magazine publisher Michael O'Doherty.
McIlroy and Wozniacki have been an item since last year and is one of sport’s most famous couples.
McIlroy is currently second in the men’s world golf rankings and Wozniacki is sixth in the women’s world golf rankings.