McLaren Team Principal Andreas Seidl admits Ferrari have had "a good advantage" at the last two races in the USA and Turkey.
Both Ferrari cars have been fitted with a new power unit which has seen them move ahead of McLaren on outright pace to close the gap to 3.5 points in the Constructors' Championship.
Charles Leclerc finished 24 seconds ahead of Daniel Ricciardo in Austin at the weekend and was two-tenths of a second faster in qualifying.
"It's a reality [that] they've made a good step forward with their package, also down to the upgrade they introduced on the power unit side," Seidl told RacingNews365.com and other select members of the press.
"That gave them a good advantage, especially in these last two races compared to us, so that's the reality we are in.
"But at the same time, it's simply important to focus on ourselves; we know that there's no upgrades coming anymore on the car side or power unit side.
"We know that there's tracks coming that will probably play a bit more to the strengths of our car. But there are also tracks at the end of the season where we will struggle compared to Ferrari.
"It's simply important we extract each weekend the maximum out of the package as it is, execute clean weekends, clean races, have a good strategy and then hopefully that's enough to battle them until the last lap in Abu Dhabi."
Ricciardo held off Carlos Sainz in the second half of the United States GP to score his fifth top-five finish of the season.
Lando Norris was slightly off the pace throughout the weekend and was forced to settle for eighth place at the Circuit of the Americas.
Seidl says McLaren achieved "what was on the cards" on Sunday.
"I think we need to be absolutely happy with the outcome of the race because I think we maximised everything that was possible for us, or even more," added Seidl
"We finished ahead of one Ferrari and both Ferraris have been really quick all weekend. So that's a good achievement.
"Also to keep Valtteri [Bottas] behind in the race is also something which we didn't necessarily expect. The reality is that Ferrari was simply a lot quicker this weekend than us. It was well embraced by the team and by both drivers."
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