The midfielder had impressed during his time at Nottingham Forest, but the size of the fee immediately raised eyebrows.
For a club accustomed to operating at the very top end of the market, it was still a significant outlay for a 23-year-old who had only recently established himself as one of the Premier League's leading midfielders.
Inside City, however, there was a clear understanding of what the club were buying.
They knew they were likely to lose Rodri and, rather than simply looking for a short-term replacement, wanted a Premier League-calibre midfielder who could form part of the next generation of the team.
Anderson was viewed as that player.
The subsequent arrivals of Ayyoub Bouaddi and Enzo Fernandez have added further quality and depth to the midfield, but it is Anderson who has perhaps brought the greatest sense of calm to a club undergoing a significant period of evolution.
Sources confirm that City have been delighted with the way he has settled.
He completed his first full 90 minutes in the 1-0 win over Coventry City on Saturday and there is a composure to Anderson that belies his 23 years. He rarely appears rushed in possession, is comfortable taking the ball under pressure and has an ability to retain it that has quickly made him an important reference point for the team.
Those qualities have been significant at a time when City are attempting to reshape themselves under Enzo Maresca, following Pep Guardiola's departure.
There is already a growing belief around the club that this evolution can work - and Anderson has played a major part in creating that feeling.
Maresca sees him as City's holding midfielder, a role that should prove hugely significant in determining the make-up of City's midfield for years to come.
Anderson offers Maresca a player who can dictate the rhythm of games, protect possession and give those around him some freedom to play.
The comparisons with Rodri will inevitably follow, but City are already feeling comforted by his presence.
That is why the £116m fee is already beginning to feel less important internally.
There is still a long way to go, but the early signs are extremely encouraging. And for a Manchester City side trying to establish what comes next after Guardiola and Rodri, Anderson's emergence could prove to be the most important piece of the rebuild.