Red Bull might have to wait until the start of the Spanish Grand Prix next month before they are able to match Mercedes, according to Daniel Ricciardo.
The reigning Constructors Champions were Mercedes' closest challenger in Malaysia last week despite a difficult start to the season, despite Christian Horner's claims that Red Bull's progress this year would depend on how much their Renault engine is developed throughout the year.
Ricciardo, who was in fourth place before he suffered a series of problems that ultimately led to his retirement in Malaysia, believes Red Bull will be even closer to Mercedes in Bahrain this week but added that they may have to until May's Spanish Grand Prix before they can challenge the front of the grid.
"I hope it's this weekend but once we get back to Europe, to Barcelona, I think we'll be more competitive, because time will have passed and we'll know much more," the Australian told Autosport.
"Our car mechanically and aerodynamically is quite good and Barcelona does reward that.
"If we're not there by then I think that's a race we'll start to show our true colours."
His team-mate Sebastian Vettel is less optimistic of Red Bull's chances this week, saying that their RB 10 is too slow.
"It's tricky. On every circuit you have straights, and at the moment it's not a secret - look at the speed traps, we are slower than the other teams, too slow to challenge them [Mercedes], Vettel said.
"We lose too much time there. That's not a complaint; fair enough they did a very good job so they deserve to be in that position.
"I think we are already much closer than we and probably everyone else thought. All we have to focus on is the fight we can fight right now.
"There is still a lot we can focus on from our side, in terms of car performance, in terms of driveability. Equally on the power front, Renault is pushing very hard and trying to make the engine more powerful.
"In a way it's a little bit similar to 2009 when we chose not to run KERS.
"But it's still a long season and the cars are early in their development. We need to be aware that anything can happen at any time.
"At the moment we seem to be making big steps. We just need to make sure that our steps continue being bigger than the steps other people are making and then we should have a say."