Since going public with their relationship in 2021, both Alex and Katie have regularly posted images of each other on social media.
In March 2023 the couple celebrated their three-year anniversary with a candle-lit dinner and on August 1, Alex posted a picture of Katie at sunset on Instagram to celebrate her birthday. "Happy Birthday to this beauty" he captioned the post.
Following his loss at the US Open against World No.3 Daniil Medvedev, Alex revealed how Katie helped him keep things in perspective.
"A big thing that I admire a lot about Katie is how she acts and how she gets herself up during matches," he said after she bowed out in the third round at Flushing Meadows.
"Her philosophy is something that I envy in a way. She is very positive. She doesn't take tennis matches for granted. She doesn't mind the results. She goes out there competing and enjoys herself. I've learned a lot from that," he explained.
"To be honest, I'm probably on the other spectrum. I live and die by the sword and matches do hurt me in ways. Over the years, I've learned that as much as it hurts in the moment, I can get off the court and the more I spend some time with Katie, we're both able to kind of forget about it and move on."
"And it's helped me a lot to not have to linger with some of these matches. I've been able to turn the page and move on and look forward to the next challenge."
As Alex prepared for the United Cup and Australian Open in 2024, he delighted fans with snaps of his Christmas alongside Katie.
As they celebrated the holiday season Alex made headlines when he landed himself in hot water after claiming he would expose his girlfriend's weaknesses if they were to go head-to-head in mixed doubles at the United Cup.
"Well, you never know until you sign on the dotted line, come that mixed (doubles)," de Minaur said on Thursday. "I could be an option (for the doubles). I have played mixed in the past with Katie, so I know all her weaknesses!
"I've watched enough of her matches to know the spots to be attacking. If we step out on court, it's just all business."
"That's pretty brave of you to say that (about Katie)," John Millman chipped in following Alex's comments. "You're in trouble. (You) might be sleeping on the pull-out in my room tonight."
Who is Alex de Minaur?
Hailing from Sydney, Australia, Alex was destined for a life in tennis. Born on February 17, 1999, he displayed an innate love for the sport from an early age. Alex quickly progressed through the junior ranks, setting the stage for what would become a remarkable professional career.
Alex's playing style is characterized by his agility, exceptional speed and his ability to chase down seemingly unreachable shots and turn defence into offence has earned him the nickname "Demon" – a moniker that perfectly encapsulates his tenacity and ferocity during matches.
With each powerful forehand, strategic volley, and spirited rally, de Minaur has amassed a legion of fans who eagerly anticipate his every move.
How old is Alex de Minaur?
Alex was born on February 17, 1999. He is 24 years old.
What is Alex de Minaur's ranking?
Alex's world ranking is currently 12. He achieved a career-high ATP singles ranking of No. 12 in August 2023 and a doubles ranking of No. 58 on 12 October 2020.
What does Alex de Minaur's tattoo mean?
Alex has a tattoo of "109" on his chest because he was the 109th player to represent the Australian Davis Cup team.