Kourtney, 40, was linked to the Grown-Ish star in September 2018, following her split from Younes Bendjima. A few months later, Sabbat said he was not dating the POOSH founder.
Although they were seen together on several occasions over the next few weeks, a source told People that there was "nothing serious" between them.
A source told the publication at the time: "It makes her feel good to have these hot, young guys who are interested in her.
"Luka is also good friends with Kendall... He’s young and is going with the flow.
"If everyone’s saying, 'Hang out with Kourtney,' he’s going to hang out with her."
Also posting to her Instagram stories, Kendall shared another picture of Sabbat in a black suit, white dress shirt and tie.
Last month, Kendall and on/off boyfriend Ben Simmons sparked speculation they had reunited again.
The Keeping Up With The Kardashian’s star and the basketball star were filmed during a New Year’s Eve outing in downtown Philadelphia Philadelphia — where Simmons, 23, plays for the local 76ers NBA team — Jenner walked alongside her ex and a group of friends to a private party at the rooftop bar Attico, according to TMZ.