The 44-year-old presenter flashed the YSL hardware while running errands in Sydney, exhibiting a pronounced limp as he walked.
Dressed casually in a khaki baseball cap from Chargrill Charlie's, grey track pants and a black jacket, it wasn't clear if the keyring belonged to Karl or his new wife.
The sighting comes after Karl was roasted by Gold Logie winner Tom Gleeson during his eight-minute acceptance speech at the Logies on Sunday night.
The Hard Quiz host took aim at the embattled anchor, declaring: ""I think the reason they ask you to do the opening is because Channel Nine has run out of stars.
"They don't have any left. They have a new rule on breakfast TV too if you are too entertaining they fire you. Am I right Karl. Is Karl here. Where is Karl?"
At this point Karl, sitting next to wife Jasmine Stefanovic, appeared visibly nervous as Gleeson went in for the attack, but not before slamming Channel Nine reality TV show Married At First Sight.
"Congratulations to Married At First Sight by the way for their monster ratings. Give them a huge round of applause.
"Channel Nine were happy to cash in on your ratings by showing off your tacky weddings and fired Karl Stefanovic for having one!"
Karl had the final word, though, labelling Gleeson a "24 carat gold tosser" during a red carpet interview.