The 16-year-old, who signed his first professional contract earlier this year, scored his first Under-19s goal at the end of last season.
However, the vast majority of his minutes were spent with the Under-17s where he capped off an impressive campaign with a strike against Hibernian at Ibrox on the final day.
He started for the Under-19s in Tuesday’s win over Kilmarnock on league duty in a lineup which included Corey Ngwenya, Luca Rankin and Ruaridh Hall, all born in 2010.
Speaking to the official Rangers website, Fergusson said: “If you look back at the end of the season, these [the Kilmarnock win] are the games you look at that you need to win in terms of the league.
“It was the same last season. We held on to a few big results, both at Under-17s and Under-19s level.
“With the Under-17s last season, we stormed the first six months and got on really well.
“But with the Under-19s, you saw it was the last day that we won it, so games like these are really important to go in and win.”
Prolific at Under-17s level last season, where he is still eligible to feature this campaign, the winger is sure to be in for a much tougher test as the Under-19s target back-to-back league titles.
On the biggest difference between the age groups, he continued: “I'd probably say the tempo and physicality.
“Against right-backs when I play at Under-17s, I feel like I can get away with more stuff than I do at Under-19s because the boys are smarter, quicker and stronger.
“It’s really good for my development playing against quicker and stronger boys.
“What I want is to be challenged. Games like Tuesday, I love it, playing against boys who are a couple of years older than me.
“I love the challenge, and it's really good. It was great to get a little taster for it, especially coming in full-time this season.
“You want to go and win as much as you can, and games like Tuesday are so important to win.
"It’s been a really good start to the season, so we need to keep pushing.”
Fergusson’s start on Tuesday evening came off the back of his Scotland Under-17s debut.
Indeed, the 16-year-old was on the scoresheet for his country last month, netting in a memorable comeback draw against Belgium.
He added: “It was a really good challenge playing against different styles of play and the best players from other countries as well.
“It was nice to score against Belgium in the last minute.”