Charles Leclerc admits it is "worrying" Ferrari do not know the reasons for the car troubles that led to his Q1 exit in Spanish GP Qualifying.
Leclerc qualified 19th in Barcelona after being blighted by handling problems, especially through left-hand corners.
Ferrari changed the whole rear end of his car ahead of the race - in which Leclerc finished P11 - but the Monegasque revealed ahead of this weekend's Canadian GP that they had failed to find a cause for his issues.
"Qualifying in Barcelona was a very particular one and I think I wasn't the only one to struggle. We need to understand these things and for now we don't have the reasons," Leclerc said on Thursday.
"This is a little bit more worrying and that's where we need to push and try to understand the reasons of it because obviously the feeling was really bad."
Leclerc's team-mate Carlos Sainz had managed to put his Ferrari on the front row in Spain, but he finished the Grand Prix in fifth after Ferrari's lack of race pace reared its head again.
Ferrari have just one podium finish in 2023 and are fourth in the constructors' championship, already 187 points behind leaders Red Bull. Leclerc meanwhile finds himself seventh in the drivers' championship on just 42 points.
The Scuderia were being tipped as title contenders in pre-season, and Leclerc has urged the team to bring updates to the underperforming SF23 as swiftly as possible.
"Overall I think all the team is not satisfied with the performance we are showing at the moment on track and it is very far off expectations at the beginning of the season," Leclerc said.
"Looking ahead we just need to keep pushing, try and bring upgrades as quickly as possible and regularly which is our aim now to try and close the gap to the guys in front and also close the gap especially in terms of race pace.
"Even though I struggled a lot in qualifying on the Saturday, the Sunday wasn't great either - and if we look at Carlos he had a great Saturday and then on Sunday we struggled again with the race pace. That's where we are trying to push at the moment."
Leclerc reiterated he still had faith in Ferrari's project, saying: "What gives me confidence though is that there is a clear direction of where we want to work and improve and this is what makes me believe in the project."
Leclerc's troubles in Spain came on the first weekend that Ferrari ran their major upgrades to the SF23, and while he thinks the team will have an improved showing in Montreal on a track that should suit their car better, the 25-year-old is not expecting huge progress.
"On this track we don't have anything new so I don't think we'll have any miracles. But we need to just try and maximise our package, understand more this package, set-up the car in order to maximise it.
"In Spain we were quite easily off the window and then we were losing a lot of performance. We have learnt a lot and pretty sure we will be in a better place for this weekend but I don't think it will be a huge step forward.
"Last year [when Ferrari finished second and fifth) we were in a very different situation. We expect Aston Martin to be very strong this weekend, we expect Red Bull to be very strong this weekend, we struggle to understand where Mercedes will be compared to us.
"We have to focus on ourselves, try to maximise our package. It's a very challenging track and with the weather, we don't really know which side it's going to go. We'll just focus on ourselves and see what we can do."
Friday June 166pm: Canadian GP Practice One (session starts at 6.30pm)7.45pm: The F1 Show9.45pm: Canadian GP Practice Two (session starts at 10pm)
Saturday June 175.15pm: Canadian GP Practice Three (session starts at 5.30pm)8pm: Canadian GP Qualifying build-up9pm: Canadian GP Qualifying11pm: Ted's Qualifying Notebook
Sunday June 185.30pm: Grand Prix Sunday Canadian GP build-up6:55pm: The Grandstand with Daniel Ricciardo and Will Arnett (via red button)7pm: THE CANADIAN GRAND PRIX9pm: Chequered Flag Canadian GP reaction10pm: Ted's Notebook