Red Bull made a big step forward with the pace of its car at the Singapore Grand Prix thanks to a raft of updates, which included a new front wing, tweaked rear bodywork and a double-DRS.
Vettel's run of form has left his team on the verge of the constructors' championship - as it now enjoys a 77-point margin over Ferrari - but McLaren technical director Paddy Lowe is adamant that the fight for individual wins remain totally open.
"They are within reach and we will never give up trying to turn that around," said Lowe, whose outfit currently stands just six points behind Ferrari in the constructors' battle.
"I think we have seen this year that if you can qualify on the front row and then have even a moderate advantage or no advantage at all, it works for you to stay at the front. So we will have to turn qualifying around."
Lowe believes that Red Bull's recent advantage is just a chapter in the ongoing development war that has raged all season. He says McLaren is working on upgrades that could get it back to the front as well.
"I don't think we've done anything wrong. It is just the war of development and it has swung during the year," he said.
"They have made a very decent step with their car, and you don't necessarily see it instantly in any particular race.
"You have to see a range of races to see where the strength comes. I think they brought their substantial upgrade to Singapore and visibly they had a lot on that race, and that has come across in the results of the last three events.
"But we have some big stuff we are working on. Whether it will be enough we don't know yet, but it will be spread across India and Abu Dhabi."
Lowe concedes that the chances of beating Red Bull to the title this year are now slim, but says that the minimum his team should target is overhauling Ferrari in the fight for second.
"I would be lying if I didn't say when you look at the points situation it is not going the right way at the moment," he said. "We would have to have some pretty stunning results and them [Red Bull] not to turn it around now.
"Of course disappointingly [in Korea] we lost second position in the constructors' championship, albeit it is only six points which is certainly manageable.
"There will be a great determination to get second place and we always like to keep Ferrari behind us. That will be the least we should want to manage out of this season."