Johannisen was particularly impressive as he roamed the Dogs defence, racking up 24 disposals, including eight contested possessions.
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He used his pace and dare to clear the defensive zone, and despite playing on some more mature opponents, he wasn't fazed by the occasion.
"Macca's told me to defend first and when we get the ball, take the game on and be brave," Johannisen said on Saturday night.
"It's just spoil as a defender, and if we win it, just go.
"We'll watch the review and we'll see a few clips that we could have done better, but we weren’t afraid of Geelong, we just took the game on."
Five talking points: Western Bulldogs v Geelong
The Bulldogs held the Cats goalless in the final quarter, as they made a last quarter charge.
But while they fell short, coach Brendan McCartney takes faith in comparing his developing team to how Geelong has grown over the years.
"A lot of our younger players do watch players at opposition clubs," McCartney said.
"What I do have is probably a better understanding than most of how those young boys were made a fair few years ago.
"So maybe I don't talk about it a lot, but mentally I remind myself that some of their great players took time to develop and had obstacles and points in their career where they had to work through it.
"The parallel for me is seeing the good in a young person and then adding the other bit to the recipe so that they become more consistent and fit the team a bit better."
