But Sane started Saturday's 3-0 Premier League win against Fulham and scored the opening goal from close range in the second minute at the Etihad Stadium.
Gabriel Jesus is likely to lead the line, but there is plenty of competition for places in attacking midfield, with Leroy Sane, David Silva, Bernardo Silva, Phil Foden, Raheem Sterling, Ilkay Gundogan and Riyad Mahrez all options.
Guardiola said he was still keen to work with Sane, but said the likes of Silva - who made just 15 league starts last season - also deserved their chance.
Germany winger Sane tapped home after 96 seconds and David Silva netted his 50th Premier League goal midway through the first half.
"When a guy has a simple ball but they make an extra pass, an extra dodge and they miss the pass, I'm angry, I'm upset with my players".
"Our aim is obviously to build on the achievements of the a year ago", Al Mubarak, City's chairman since the club was bought by the Abu Dhabi United Group in 2008, said in a statement.
City were soon back on the front foot, though, and Aguero should have done better when he got his head to a pinpoint aerial pass into the box by Silva.
Silva's goal epitomised their approach.
He said: "It's well-known we're delighted with him and would like that to continue".
- Fulham have registered their second worst start to a Premier League campaign after five games (4pts, -5 goal difference); only bettering 2011-2012 (3 pts, -3 goal difference).
Man of the match Bernardo Silva played in the Belgian's position against the Cottagers and the Portuguese star was simply majestic at times.
The early goal should have been an alarm bell for the away side to change their game up and show the opposition a bit of respect, but they continued to try and play out from the back and were caught out on almost every occasion.
City manager Pep Guardiola made a point of greeting his mascot with an embrace as she came off the field and took time out of his pre-match preparations to chat briefly with Vera, who has been a City supporter for 85 years and still attends games with Olga, son Danny and son-in-law Roger.