Jenson Button believes his McLaren team are 'miles behind' pace-setting rivals Mercedes and have no chance of catching them in this weekend's Spanish Grand Prix.
He said on Thursday that he thinks it will be "months" before any other team has a chance to catch and match the pace and performance of front-runners Nico Rosberg and Lewis Hamilton.
"We're miles behind the Mercedes, but we're in a good little scrap with five other teams," Button told reporters.
"We're not worried about later in the season. We feel we can develop faster than most teams.
"We're adding updates to the car all the time, some bigger than others, but I think for any team to find a second is a big ask over the next couple of races.
"And that's with Mercedes standing still. And they're not going to do that. It's going to be tough and we've got to be realistic about it.
"Some people might over-deliver and we might see in two or three races that we're able to fight them, but I think it would be very impressive for any team to achieve that."
Drivers championship leader Rosberg and his team-mate Hamilton have dominated the opening four races of 2014 for Mercedes.
McLaren, who took second and third in the season-opening Australian Grand Prix thanks to strong drives from Kevin Magnussen and Button, have slipped back since that promising start.
Button finished a lap behind Briton Hamilton, the 2008 champion, at the Chinese Grand Prix and Dane Magnussen has also struggled.