Kimi Raikkonen admitted that he is still somewhat uncomfortable in the Ferrari F14 T, after the Finn endured another difficult race in Monaco last week.
After qualifying seven tenths slower than Fernando Alonso, the 2007 World Champion made a great start to the race and found himself in third place when Sebastian Vettel was forced to retire early on.
Raikkonen seemed to have a great chance of finishing on the podium for the first time this season before his race was ruined when he was involved in two collisions that required him to make unscheduled trips to the pits on both occasions.
His strong showing in the opening stint in Monaco aside, Raikkonen has been consistently outpaced by Alonso throughout the season and after this weekend's race in the Principality, he admitted that the Ferrari remains a challenge for him.
"I'm still not happy with the car - the race was better than qualifying but we still have a long way to go to where we want to be," Raikkonen said after the race.
"We need to improve in many areas.
"We've done a lot of things already, particularly with the engine, but we're still lacking speed.
"We have to compare to Mercedes and they're still quite a way ahead of us.
"We know what we have to do but those things will not be easy to fix. It just takes time.
"We're going forward all the time but other teams are improving also.
"We know where the weaknesses are but if it would be easy everybody would have a fast car."