The Portugal internationals only appearance for the club since his move from Juventus was in the final minute of Citys 3-1 win against Bournemouth in August.
Pep Guardiolas decision to move for the 25-year-old raised eyebrows in some quarters given Kyle Walkers revival in the second half of last season, as well as Citys arguably more urgent need for a centre-back.
But Guardiola was determined to strengthen at full-back and feels Cancelo represents a more technically sound, defensive-minded option than Walker.
Cancelos greater experience in Europe is also considered a valuable asset as City have come unstuck in recent years against the likes of Tottenham, Liverpool and Monaco in tight knockout fixtures.
The importance of full-backs in Guardiolas system is well known and Walkers recovery pace is seen as pivotal to the Spaniard, particularly when teams threaten to counter City.
But, while Walkers overlapping runs are perfect for a City side that recycle possession with ease against weaker Premier League sides, its a riskier tactic against Champions League outfits that can turn defence into attack with one pass.
Guardiola feels that Walkers determination to get in behind can leave Citys defence isolated and that Cancelo can offer the same attacking threat but through different means.
Cancelo provides an attacking threat but his work in the final third can be produced from deeper positions, meaning Citys overall structure is more defensively sound even when theyre in position.
The city project has been geared towards winning the Champions League and Cancelo was signed with the competition in mind.