Alex Glenn says that six weeks of brutal pre-season training has brought the new-look Broncos forward pack together as a unit.

Glenn likes Bronco pack's mentality

They're the new boys pushing for a place in Wayne Bennett's Brisbane team for Round 1 but experienced forward Alex Glenn says the host of new forwards at the club is pushing the senior players to reach for greater heights in 2015.

The Broncos will go back to the future on Saturday in Mackay when Bennett takes charge of his first full Brisbane team in seven years for a trial against the Cowboys where a host of new recruits will be given their chance to impress.

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Adam Blair, Mitch Garbutt and James Gavet are all looking to push established and highly-credentialed Brisbane forwards out of the 17 for Round 1 while youngsters such as Joe Ofahengaue, Francis Molo and Ajuma Adams are eyeing off elevation to the top grade.

With Ben Hannant and Martin Kennedy both leaving the club in the off-season Glenn conceded that he wasn't sure how long it would take the new pack to come together but said that six weeks of pre-season punishment – and time spent sipping coffees – dished up some surprising results.

"The last six weeks before Christmas we really came together as a pack. There was only me, Todd Lowrie and Andrew McCullough who had been here for a little while and the rest were all new boys and the way we all came together in that six weeks surprised me a fair bit," Glenn told NRL.com.

"The new boys all gave their 100 per cent and whatever the task was at hand there was no whinging or anything. They just got the job done and did what was needed. From a forward pack you always want them to be that hard engine room driving the team forward and they've been doing everything the coaches have been asking of them."

Captain of the Broncos' inaugural under-20s team in 2008, Glenn is now inching towards 150 NRL games but is entering his seventh season expecting more of himself.

The 26-year-old Kiwi international spoke of the qualities he admires most in a fellow member of the forward pack and admitted that there have been areas of his own game that haven't lived up to those expectations in recent years.

"Everyone can play footy when they're fresh; it's the part when it's 20 minutes in and everyone's trying to get their breath back that you want to know that your man inside is always going to cover you in defence or is going to take that next run for you," Glenn said.

"You always want that from a player, who is going to do the hard yards when he's tired let alone when he's fresh, always putting his body on the line. That's something that I want to work on as well.

"My mentality over the last couple of years sometimes, when I'm tired I sort of go into my shell so I'm trying to take myself out of my comfort zone and push myself harder so my teammates can trust me out on that field when I'm tired as well."

Although he is unlikely to figure against the Cowboys this weekend, the addition of Adam Blair promises to bring a much-needed hard edge to the Broncos pack in 2015.

Although he had been the subject of heavy criticism throughout his three-year stint at the Wests Tigers, Glenn said the influence of Blair on the training paddock is already having a telling effect.

"We haven't played any games but you can see the intensity that he puts into his training and it's great for myself and also the younger boys to learn off that," Glenn said.

"They're very strong habits and when you're training hard it always leads into the game, making sure you're executing well at training, and he brings that to our team.

"He's been in grand finals, he's been a regular Test player and he's one of the best defensive wrestlers in the game so he brings a lot to our pack.

"He's teaching us a few tactics and stuff on how to be dominant in the wrestle. Obviously wrestling's a big part of our game nowadays and being dominant in the tackle so he brings a lot to that and just his experience in general."

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