Leuenberger will have his first competitive hit-out in almost 11 months on Saturday night, when he plays half the NAB Cup match against GWS at Wagga Wagga.
It completes the long road to recovery following an Achilles injury that restricted the 24-year-old to just the first three matches of 2012.
For Rockliff it means reuniting with a class tap-ruckman in the middle of the ground.
"He's a massive benefit for us and it is great to see the big fella out there, he's been through a fair bit in the last 12 months," Rockliff said at training on Friday morning.
"Now he gets a chance to run out there with us on the weekend. It's great to see him back."
It was no coincidence that as Leuenberger hit career-best form in 2011 a young Rockliff also benefitted, winning the Lions' best and fairest.
He said seeing the 204cm giant in the centre square again was a huge lift to the entire midfield.
"I think we saw at the end of 2011, those last 10 games he was one of, if not the, best ruckman in the competition," Rockliff said.
"The ability for him to get up and give us first use in the midfield, I think that's something we lacked last year - taking nothing away from Huddo (Ben Hudson), he was fantastic for us.
"Leuey is a running, athletic (ruckman, who) covers the ground well. He's pretty much a fourth midfielder for us but also gives us the ability to get our hands on the ball first."
Leuenberger took no part in the light skills session on Friday morning, just walking laps with ruck coach Jamie Charman.
Assistant coach Mark Harvey said that was no concern.
"Just with the wet tracks at the moment … he trained yesterday, had a private session - he's ready to play," Harvey said.
"His first introduction will be a half of football and he'll get two full games after that."
Harvey said the Lions were far from settled on their best 22 but would try and establish that for the following week's match against Collingwood.
"We're the third youngest playing group in the competition and we have to try things and see if we can get a different angle on our team," Harvey said.
"The best part about it is some of our younger players, first and second year, are putting pressure on for selection. I think we'll create a lot of interest in the competition this year, that's what I do think."
Matthew Leuenberger is a ruckman in NAB AFL Fantasy. He averaged 56.7 points in 2012. Register your team at our AFL Fantasy Hub.
Michael Whiting covers Brisbane Lions news for AFL.com.au. Follow him on Twitter: @AFL_mikewhiting