It is the Jordan Ridley riddle.

How does a player who had played just nine games over three seasons at Essendon finish his fourth year as perhaps the club's most influential member?

How does a 21-year-old who wasn't a certain starter for round one end up winning his team's best and fairest?

How does someone who was being trialed in the midfield the previous season then become one of the game's best intercept marking defenders and a member of the All-Australian top-40?

If Ridley, the Bombers' shining light of a horror 2020, surprised you last season with his assured performances in an under-fire defence, then you weren't alone.

"To be honest if you'd told me before the year I'd even have played every game I would have told you you're kidding yourself. I was coming into the year with pretty low expectations," Ridley told AFL.com.au.

"Basically the only thing I was trying to do was lock myself into the team by the end of the year and I was fully expecting to be playing a lot of reserves throughout the year to do that. I completely surpassed where I thought I'd get to."

There were a few sticking points before Ridley's rise, which has continued this season having last week been the Bombers' best in their loss to Port Adelaide. The first was in his debut season at the club, when he suffered a back stress fracture and then syndesmosis ankle injury that ruled him out of the end of the season. That was frustrating; all he wanted to do was show why the Bombers had used their draft pick No.22 to grab him.

That wait stretched into 2018, when Ridley made his debut with a poised 25-disposal showing in a surprise win over Geelong. He played another two games that season, and found it difficult to edge past experienced pair Michael Hurley and Brendon Goddard as tall interceptors.

It was 2019 when the challenges set in. He played six of the first seven games at AFL level before being losing his spot and not returning. He was used as a midfielder for a period, including a stint on the wing that didn't work, and left the season unsure where his career sat.

"I felt like I couldn't hit form and I couldn't do anything right. I was probably glad that season ended so I could hit the reset button and start again," he said.

"The main thing was just the mental side of my game probably wasn't where it needed to be. I found I wasn't really trusting my instinct or anything I do naturally and I was second-guessing decisions I'd make on the field and overthinking everything when I was out there. Towards the end of that year it started to turn a bit and I tried to take the shackles off and let go a bit."

He changed his approach over the pre-season heading into 2020, too. He headed to America and trained there with teammate Andy McGrath and ramped up his training extras across the pre-season. There was more kicking, marking and weights as he headed into his fourth season out of contract knowing he had plenty to prove.

"I was fully aware it was probably a make-or-break year for me. I was trying to put that on the backburner and not really think about what I was doing too much. The main thing was that I just wanted to go back to having fun playing footy and enjoying myself and let what I naturally do take over a bit," he said.

The first signs of that were in the pre-season competition, where Ridley tallied intercept disposals at will. Then, his round one game against Fremantle, when he took nine marks in Essendon's win, solidified his position and established his confidence. From believing he could be up to the level without knowing for sure, Ridley now had the evidence. With every outing more parts of his game emerged.

There was the marking but also the courage – his two back-with-the-flight efforts against the Bulldogs caught the attention of the Bombers' coaching panel – and his surety by foot out of defence. Other clubs, starting with Brisbane, began to attempt to chop off his run at marks. Even after a breakout game Ridley would text coaches on Sunday night asking when they could catch up to watch his edits the following morning.

Everyone at Essendon describes Ridley as understated, and his low-key demeanour has been central to his consistency, but before last year he had been pushed to be more outspoken, encouraged to be more emotionally involved.

"My mind's racing sometimes [on the ground] for sure, but generally I'm a pretty relaxed sort of guy and even pre-game and in-game I'm pretty relaxed. Most of the time what you see is what you get," he said.

"I definitely got a lot of feedback around being more vocal and louder on the field. I'm probably naturally a pretty quiet person so it did feel pretty unnatural to me and I had to find a balance between me being me and being vocal enough to help the team back there.

"The big one for me was James Kelly coming in as the backs coach last year, I worked super close with him all year and he really helped me find that balance. It's still something I'm working on now."

Kelly, who quit his role as an Essendon assistant in January to spend more time with his family, said Ridley's quieter temperament had meant he was underestimated.

"Everything was a bit underrated about him. His toughness was underrated. His calmness was underrated. His kicking and marking was underrated. His competitiveness was underrated. But then as last year rolled on everyone was like 'Oh my gosh, this guy is a superstar'," Kelly said.

"Perception's everything in footy and he changed his perception. His calmness became a weapon for him. The things he got hammered for in 2019 were the things he got patted on the back for last year and he never got ahead of himself."

Ridley let others get excited.

Essendon offered him a four-year contract, which he accepted, but not before Brisbane had also tabled a long-term offer, with his sister moving to Queensland over summer and training with the Firebirds netball side. Ridley, who was drafted via the Oakleigh Chargers, didn't long consider the Lions' approach, instead keen to steer Essendon's road back to the top as they start this season 0-2 under new coach Ben Rutten.

"It was very flattering that they thought of me that way but I was never super interested in it, mainly because I really love Essendon as a club. A big reason was the people at the club and a lot of my close mates are at the club and I couldn't imagine leaving them. I love the idea of playing at a massive club and building something with my mates who have come through," he said.

"Having such a young team is super exciting to think we can build something ourselves and we can become that next great Essendon team if we want to."

Two of those teammates are McGrath and Ned Cahill, with the trio living together in Albert Park. They occasionally whip out some board games, but a new addition to the house might have finally found a way to break Ridley's renowned composure.

"We bought a Nintendo Switch probably a month ago and we play it just about every night. It can get pretty heated," he said. "Ned tends to tip me over the edge sometimes when he's losing."