Hawthorn young gun Jack Ginnivan has admitted he needs to “grow up” after sparking the ugly post-match war following the Hawks’ loss to Port Adelaide last week.

Ginnivan lit the fuse for a hostile clash against the Power with his infamous comment on former teammate Brodie Grundy’s Instagram post.

Port Adelaide felt disrespected after Ginnivan wrote “see you in 14 days” on Grundy’s photo.

After Port walked away with an epic three-point victory, tempers flared as veteran coach Ken Hinkley taunted Ginnivan before being involved in an ugly verbal stoush with Hawks captain James Sicily.

Hinkley was fined $20,000 for his role in the post-match exchange with Sicily, who 7NEWS.com.au revealed on Thursday said Port had been a “nowhere club for eight years”.

Ginnivan privately admitted to club leaders that he regretted the social media post and, speaking publicly for the first time since the Hawks’ finals exit, the 21-year-old conceded he needs to be a bit “smarter”.

“Upon reflection, it probably wasn’t the smartest idea, but the leaders and coaches had my full support and they backed me in,” he told 7NEWS chief AFL reporter Mitch Cleary.

“Yeah I just got to grow up I guess and be a bit smarter.”

Ginnivan was central to the Hawks’ rise this season with the former Collingwood premiership player’s energy and enthusiasm galvanising the young squad.

But he also brought a series of unwanted headlines with him.

The night before the Hawks’ elimination final win over the Western Bulldogs, Ginnivan was having dinner with mates at a Richmond pub.

And then there was the social media post.

Ginnivan’s admission follows similar comments made by his former coach Craig McRae after Collingwood’s win over Brisbane in last year’s grand final.

Ginnivan had an unusual preparation for the premiership decider with 7NEWS reporter Mitch Cleary revealing the 20-year-old was at the Moonee Valley races the night before.

When asked if he was happy about Ginnivan going to the races before the game, McRae said: “Read the room, Jack.”

“You’ve got to grow up, but you’ve got to make mistakes to learn from them,” he added.

Ginnivan, who missed the first two matches of 2023 after he copped a club-imposed suspension for taking illicit drugs, was traded to Hawthorn just three weeks after winning the premiership with Collingwood.

Ginnivan is gearing up for his first Brownlow Medal night and will be hard to miss in his white jacket.

“Sammy (Sam & Ko) looked after me with the white, I didn’t have much say, he wanted to do something a bit different and I’m always trying to do something a bit different ... hopefully it scrubs up alright.”