When Richmond defender Nathan Broad injured his shoulder two days out from round one, he could not have imagined the positive impact it would have on his season and his career at Punt Road Oval.

Out of contract at the end of the 2017, on the fringe of selection and without a clear understanding of what type of player he was, the signs were not good for the mature-age recruit from Western Australia.

But a 10-week stint in rehab under rehabilitation and conditioning coach Rob Inness changed everything, and he will enter Saturday night's preliminary final with a fresh one-year contract for 2018 and a crucial role in arguably the game's best back six.

VIDEO: Broad’s 2017 highlights

"It's definitely improved my game. I don't know how, but I came back feeling like a better player," Broad told AFL.com.au ahead of the Tigers' preliminary final clash with Greater Western Sydney.

"I don't know if I wouldn't have been able to slide back into the AFL without it. It's hard to say, but I definitely feel like I came back a better footballer, that's for sure.

"I ended up putting on extra weight, I got a lot stronger and a lot fitter. So it was like a mini pre-season.

"It made me mentally stronger too. You're out of contract and part of your season's gone, your team is flying. All those things come into it and you're in rehab."

Broad, who has played the past eight games at AFL level, injured his right shoulder two days before round one, landing on his head during a drill and injuring his AC joint.

If he hadn't injured himself, he would have been starting the season in the VFL and fighting an uphill battle to find a role at AFL level.

"I didn't know exactly what I was and the club didn't know exactly what I was, if I was that running defender or a lockdown player," he said.

"We had a pretty strong back six at the time as well, so I would have started in the VFL and worked my up I reckon."

While Broad would have done everything possible to earn a chance, he can see now that he had shortcomings as a player and completing a stint in rehab gave him a chance to address them.

He sat down with backline coach Ben Rutten and asked what attributes he needed to be a better player at AFL level.

More aerial power to help him in contests with key forwards was number one on the list when he reported back to Inness. 

"We did a lot more core leg stuff because I still wanted to keep my running power up, but then a lot more technique stuff in marking contests," Broad said.

"It was a bit of one-on-one training in that rehab group. I might have been able to build the speed if I was playing, but the strength side probably not.

"The training load when you're playing drops off, but in rehab it gets increased. So I probably wouldn't have been as strong in the marking contests if I didn't do the rehab."

Since returning at AFL level in round 17, Broad has held his own in battles with opponents as diverse as Nick Riewoldt, Luke Breust and Toby Greene.

It has been a massive lifestyle change for the 24-year-old, who was an apprentice plumber before he joined Richmond as a mature-age recruit from WAFL club Swan Districts two years ago.

While he is not able to complete his apprenticeship while playing, he spends his Wednesdays at Rod Laver Arena on the tools in a work experience arrangement that he says gives his life a good balance.

On Saturday night he will play his 11th game in front of more than 90,000 fans. He will man a small forward like Greene, or a big man like Rory Lobb, moving instinctively between them as part of a team defence.

"We rotate a lot so you don't always have the same man and I need to play on both talls and smalls," he said.

"My role does change up a bit from shutdown to sometimes even spare, but I'm loving the role at the moment.

"The shutdown roles keep me engaged in the game a little bit more and I know I've got to do my role for the team, then other days I might not go to anyone, it'll just be play footy."