Jonathan Giles learned about patience at Port Adelaide, the first of three AFL clubs the ruckman has been a part of.

Giles was drafted by the Power in 2005, spent four years at the club without managing to secure a senior game, and was then delisted. He went back to the SANFL, won a best and fairest for Sturt, and got the call-up for fledgling club Greater Western Sydney as it assembled its list.

He was the Giants' first-choice big man until Shane Mumford lobbed on the scene last year, which forced him back the NEAFL team. Fighting for a senior spot isn't new to Giles.

So his four-month stint in Essendon's VFL side this year, despite the Bombers' desperate need for an option in the ruck, was frustrating but he had been in that position before. 

"I came to Essendon and obviously wanted to make an immediate impact from the get-go, and when I didn't get selected I was disappointed at the start of the year," he said. 

"But from my previous experiences at Port and the Giants, I knew there was only one way to react and that's to train hard and play better. That's all you can do." 

Giles was traded to Essendon last year, after also considering joining Adelaide. He couldn't see himself getting back into the Giants' team, liked the idea of playing for a big Melbourne club and saw some of the Bombers' brighter young players on the horizon.

But Giles hasn't had the sort of senior exposure he might have hoped for. Despite the Bombers' woes in the ruck after losing Paddy Ryder to Port and then Tom Bellchambers to injury, they turned to ruck/forward Shaun McKernan instead of Giles.

After McKernan was beaten in round 16 by Todd Goldstein, coach James Hird defended his selection, saying Giles needed to compete more around the ground before winning his first game game in red and black. 

"When Tommy unfortunately went down they went with Shaun and he had a good crack in there. I just had to keep working hard, like I did all year, and not doubt myself," Giles said.

"I know a lot of the spotlight was on why I wasn't playing, but it doesn't really affect me. I just went about my normal business. It was probably more my friends and family who were asking what's happening, but for me I knew what I had to do.

"The only way I was going to get in that team was to keep improving and force my way in." 

Hird's message was consistent throughout: he wanted Giles to follow the ruck contests at ground level, compete there, show second and third-efforts, and be an extra midfielder. For Hird, it wasn't enough to just win the tap-outs, or occasionally drift forward.

"I was doing extra sessions to get my fitness going, and extra hands sessions to get them going too," Giles said. "I started to do more things to put pressure on the selection table that I was playing better and training better." 

As the football world asked why the Bombers weren't playing the 27-year-old having signed him only months before, Giles finally broke into the senior team against the Western Bulldogs in round 18. 

He followed that up last week against the Giants, who he played 51 games for, with an excellent display. He had 17 disposals, 22 hit-outs, 11 clearances and seven centre clearances. 

The last Essendon player to have seven centre clearances in a game was Dyson Heppell in round 19, 2013.

"In the ruck you have to be competitive and win your hit-outs to give the midfielders first use, but then I've got to be following up and doing all the second efforts. 'Hirdy' was happy with how that went and it's part of my game I'm improving and working at pretty hard," he said. 

Giles wants to use the last month of Essendon's season to take some momentum into the pre-season and 2016. His next challenge is in-form Adelaide big man Sam Jacobs, as the Bombers meet the Crows at Etihad Stadium on Saturday. 

"I rate Sammy very highly, and I've seen a lot of him play," Giles said. "I've followed his career really closely and he's really hit his straps in the last few years. He's definitely a key to the Crows, and I'm looking forward to the challenge."