A few hours later Wozniacki arrived for her media call, after dispatching Romanian Alexandra Dulgheru 6-1 6-0 in the quarter final and was happy to play along with the storyline.
"So he's stalking my Instagram now, that's good to know!" joked the Dane.
"I don't know, he should ask me himself."
During his own press conference, Johnson admitted he was wary of the reaction to his interaction with Wozniacki, especially in light of the Chris Gayle affair across the Tasman.
"I guess with everything that's going on at the moment, with what's happened in Oz with the cricket, I got a few messages saying why is he getting away with it?" said Johnson.
"But you've got to give her credit really, she was easy going, played along with it and I guess it says a lot about who she is."
He remained impressed with the way Wozniacki - who is one of the highest earning sportspeople in the world and is the subject of intense global media scrutiny - had the ability to not take things too seriously.
"That was cool, unbelievable," said Johnson. "I got asked if I wanted to come in and sit in the room and I thought `well, let's see what she's like'.
I pulled up a seat and yeah, she seemed to be pretty cool. Pretty easy going, which is awesome."