Day and wife Ellie are expecting the birth of their third child around the time of the World Cup.
Leishman and his World Cup partner Cameron Smith spoke to Australian reporters on a teleconference this morning and said Day wanted to make the trip to Melbourne but didn’t want to risk missing his child’s birth.
“When me and Cam had a practice round with him at the PGA [Championship] he was still undecided then," Leishman said.
“He was trying to do everything he could to be down there, leave it as late as possible but he was disappointed.
“He really wants to be down there but just with kids and schedule, it’s hard. He left it to the last minute to let me know that he wasn’t going.
“Any time your wife is pregnant, you’ve got another baby on the way, it’s something you never want to miss.”
Leishman and Smith will be the highest ranked team at the World Cup of Golf.
Leishman said returning home to Australia each year to compete is very important to him along with notching his first victory in a major event on home soil.
“It’s certainly a priority of mine to be there and not only support Australian golf. I remember going to the events when I was a kid and watching Greg Norman and Ian Baker-Finch play and Wayne Grady and all the guys came back.
“I’ll never forget that and that’s something that I want to give the kids as well.
“I think they need to see us play in person.”
World No. 22 Leishman is the highest ranked confirmed starter for the World Cup, ahead of England’s Tyrell Hatton, American Kyle Stanley and Smith.
“It’s probably a little bit disappointing but I guess the timing of it being the week of thanksgiving, particularly with the American guys, it’s a tough one for them to leave home for.
“Me personally, I’m not going to let that put a dampener on the tournament or, hopefully, any success that we have there. It’s still going to be a great field on an unbelievably good golf course.”
The World Cup will mark the first time Smith has represented Australia as a professional.
The Queenslander – who enters this week’s Tour Championship still with a slim chance of winning the FedEx Cup – said making Australia’s World Cup team was the second of his two main goals for 2018.
“I knew it was a World Cup year obviously,” he said.
“One of my priorities was to get into the top 50 to get into that Masters field and then secondly was to get on this team so to tick both of those off in one year, it’s just been an unreal year.”
Leishman will play the Australian PGA on the Gold Coast the week following the World Cup while Smith said he’s likely to play three events in the Australian summer.
The 25-year-old will join Leishman at Royal Pines to defend his PGA title and said he is also a likely starter at the Australian Open in Sydney from November 15-18.
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