In the sweet photos, the chef, 46, planted a loving kiss on Moore's forehead as they enjoyed the tennis match together.
The brunette beauty stunned in a black sweater draped with a patterned scarf and dark sunglasses, while her man rocked a white t-shirt, light blue blazer and a baseball cap for the hot summer day.
The twosome have been going strong for several months after first being seen out together during Paris Fashion Week in March. As OK! exclusively reported, the new romance has Moore's daughters Rumer, Scout and Tallulah Willis a bit worried.
"Trouble is, Daniel is known in Manhattan circles for being a major player, and with her history, that’s the last thing Demi needs," the insider revealed about the New York restaurant owner, adding, Moore "clearly has a weakness for younger, edgier guys."
"Now her friends and family fear things could end badly again," the source explained. "Her daughters and the rest of her inner circle are all concerned that Humm's just using her for fame."
"They’re pleading with their mother not to get carried away, but she’s beyond smitten," the insider revealed of the A Few Good Men star's relationship.
Moore's new love comes at a somewhat difficult time, as ex-husband Bruce Willis has been diagnosed with aphasia. “Right from the get-go, Demi dropped everything to help. She’s been his rock," the source said of the former couple, who split in 2001.
The Striptease star “is in constant touch with Bruce. She calls him all the time, whether it’s about where to get the best treatment, tips on staying positive or updating him on the latest with their girls.”