The young footballer and university student died on Monday after he was allegedly punched in the head during a brawl at a Diamond Creek pub on Saturday night.

His father Matt Cronin has labelled the attack a "coward's punch" that claimed the life of his "beautiful boy".

The Cronin family spoke to a crowded room of mourners gathered at the Lower Plenty Football Club in Montmorency on Tuesday evening.

Speaking from a small stage, Mr Cronin held on to his wife Robyn's hand. His son Lucas held her other hand while his daughter Emma rested her head on his shoulder as he spoke, crying softly.

The grieving family all wore shirts emblazoned with the Lower Plenty Bears logo, the team their son played for just hours before he was embroiled in what would be a fatal fight.

The small club room was packed with young footballers and their parents, people spilling outside the door.

"We said goodbye to Patty yesterday," Mr Cronin said, his voice trembling. "He's just our beautiful boy, our beautiful baby boy."

His words were punctured by sombre silences, deep breaths only interrupted by sobs among the more than 100 people gathered.

"Only on Saturday was I talking to him about uni. He was in second year uni studying to be physio. Because everything he did was good."

He spoke of the incredible support the family had received from the Lower Plenty football club and the wider community.

"This isn't about the events that are going to unfold later tonight," he said, referencing the arrest of a 33-year-old man in relation to the brawl. "This is about just sharing our love for him."

"Our hearts are broken. He will forever be in our hearts and forever be our baby boy."

His wife Robyn also briefly spoke about the shock of losing her "baby".

"He hated that I babied him," she said softly before going on to say he was her "heart and soul."

"Our hearts are just blown apart," she said. "And we don't know how we'll do it but he'll help us, he'll help us everyday."

Patrick's brother Lucas spoke briefly of his joy at playing in the same side as his brother.

"I'm forever grateful for that one game we got to play together."

"Despite the events we're going to carry on with the game this Sunday," he said.

"And because Pat was so much more than a footballer, anyone and everyone is welcome to come down and honour our fallen brother."

After the family spoke, players for the Lower Plenty Bears hugged and comforted each other, before running onto the football field for a training session.

Under the sparsely lit field, the young men clasped each other's shoulders as they stood in a circle before cheers of "For Patty" echoed across the ground.

Past AFL player, coach and family friend Terry Wallace said education was vital in curbing one punch attacks and senseless violence among young men.

"If it can happen to the Cronin family, it can happen to anyone, anywhere, anytime."