The 20-year-old, who hails from the remote outback town of Yalgoo, 500km north-east of Perth, played his second game for Fremantle on Sunday against Essendon.
He debuted in round 23 last year when many of the club’s stars were rested ahead of the finals.
While Simpson has coped better with the everyday requirements of being a professional footballer in 2014, that wasn’t so much the case in 2013.
Lyon said he had displayed strong growth this year, both on and off the field.
“To come in from the outside, everyone dreams about playing AFL footy, but then the harsh realities kick in of the day to day commitment and Josh has come to grips with that,” he said.
“He’s still not perfect, but not many of us are.”
Lyon said the midfielder/forward was picked on merit for the game against the Bombers.
“He’d been in our top two the last few for Peel (and) his training has been really strong,” he said.
“It was important he wasn’t given the opportunity, he earned the opportunity and he will have to continue to earn it.
“It brings a smile to your face when the crowd is roaring and you see him doing okay.
“Hopefully it fuels his belief that it’s worth it and that he can really play at this level.”
Leadership group member Lee Spurr echoed his coach’s comments about Simpson, adding he had impressed all at the club with his turnaround after some issues in his first season.
“Josh had a long summer, he came back and he decided to buy in,” Spurr said.
“He trained hard and he’s been performing at Peel week in, week out and playing his role and executing.
“He’s been doing all the little things right, and that’s what matters.”
Spurr said everyone at Fremantle already knew what Simpson could do with a ball in his hands, but it was the defensive aspect of his game the club wanted to see come to the fore.
The defender said Simpson showed immediately that he was willing to do the team thing when he entered the game at the start of the second half.
“For him to come into the game, and against Essendon, who are a quality side, to lay some really strong tackles and apply pressure is exactly what we wanted from him,” Spurr said.
“The disposals and the goals aren’t important, it’s about coming in and playing your role, and Josh did that.”
