Assombalonga arrived at Forest from Peterborough United with no prior experience of playing Championship football and he needed to show that he could make the grade in the second tier.
He has certainly done that in his first season at the City Ground, with the striker now considered one of the most dangerous front-men outside the Premier League.
Assombalonga is still Forest's top scorer, despite picking up a serious knee injury back in February, and his total of 15 goals is hugely impressive for a player who still has time to develop.
The rise of Ben Osborn has been one of the major positives to come out of Forest's season and there is, understandably, great excitement about his future at the City Ground.
Osborn looks one of the most promising youngsters in the entirety of the Football League and he will stand a chance of winning the club's Player of the Season award when it is voted for.
The midfielder is a technically adept operator, who has all the skill required to go right to the top, and he looks set to be key for Forest for the years ahead.
Osborn has made 34 appearances for the Reds this term and he will only be more important next campaign, as Dougie Freedman looks to put together a promotion winning squad.
Although Walker may not be an established member of the Forest starting line-up yet, he has done his reputation no harm with his displays in the club's development side this season.
Walker has been a regular scorer at reserve and Under-18 level for Forest and looks to have the capabilities to be the main man, in an attacking sense, over the years to come.
He has already made two appearances under the stewardship of Freedman and that total is likely to increase next season, where he will be hoping to have a prominent role to play.