Parkinson has rewarded Theo Opperman's blistering under 18.5 form with his first senior game against Cobden on Saturday.

Opperman will replace Cooper Hoffmann as the Blues' only change after a two-week hiatus.

"He'll go through our midfield. He's pretty versatile and has played back and forward as well as centre in the under 18s," Parkinson said.

"We just couldn't ignore him any longer. He's been in great form.

"He's been on our radar for a while."

Parkinson said Opperman, a regular in Merrivale's Warrnambool and District Cricket Association division one side, was accustomed to senior sport.

"I think he's been playing division one cricket since he was 15, so he'll hold no fears about this," he said.

"He's a good-sized kid for his age and will hold his own.

"He's played a lot of cricket through the summer and he's been working really hard."

Parkinson said Warrnambool was wary of Cobden despite its last-place standing.

"You can say they're bottom of the ladder but we're only four points ahead of them," he said.

"They'll have no fears playing us." Koroit, meanwhile, will replace the injured Jarrod Korewha and premiership player Alex Pulling with Tim McPherson and Greater Western Victoria Rebels-listed Tom Baulch.

Saints coach Chris McLaren said McPherson was "the best full-back in the league".

"He really stiffens us up down back, which is great. He gives us experience," he said.

He said Baulch was an exciting prospect.

"His running ability is a real highlight," McLaren said.

"He's 193 or 194 centimetres and can play on the wing or forward and is nice and versatile.

"He's still learning the game and has played only two senior games but he has some great attributes. He played down back for us when we lost a few to injury against North Warrnambool Eagles and he did a really good job for us."

Hamilton Kangaroos has named towering tall Lachie Waddell to return and is expected to hold down a key position post while another tall in Jack Hickey has also been selected.

Camperdown, meanwhile, will be without three Melbourne-based players who are trapped in the metropolitan area as a result of COVID-19 restrictions.

Jack Williams, Judah Dundon and Jason Robinson are all unable to play while the Magpies have drafted in Charlie Lucas, Charlie Brett and Dom Absalom.

Absalom will make his senior debut after strong under 18.5 form while Lucas will return from a hamstring tear suffered in Camperdown's round three.

"He'll play through a wing. He uses the ball really well, he's nice and composed and reads the play well," he said.

"He's playing well. We've kept an eye on him and thought we'd give him a chance."

MORE TO COME - FULL TEAMS YET TO BE CONFIRMED BY CLUBS DUE TO TECHNICAL ERRORS

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