Fernando Alonso reckons Lewis Hamilton's chances of winning the title have been dealt a blow by Sebastian Vettel's recent success.
Ahead of the Singapore Grand Prix, the entire Formula One field was chasing Alonso in the hunt for this year's Drivers' Championship title.
But with Vettel claiming back-to-back wins in Singapore and Japan, they were now chasing two drivers, Alonso and the German.
"I think it is more difficult for Lewis because now it is not only one driver ahead that you need to take points from," Alonso said.
"We [Alonso and Vettel] are two with more or less the same, and [Hamilton] is back, so the chance is a little bit lower."
The 31-year-old, though, refused to write off Hamilton's bid as there are still five races remaining with 125 points to play for.
"He still has the possibility. If we see the form of McLaren and Lewis from before Japan, there is still plenty of time and plenty of points to do it."
Arriving in Korea, Alonso is leading the Championship by four points ahead of Vettel while Kimi Raikkonen is third, 33 points further back, with Hamilton five behind the Finn.
Vettel, though, has also warned against counting Hamilton out of the title fight.
"I think they are still fighting for the championship. I think that is their target, or has to be their target," said the Red Bull driver.
"I think if you look at the races we had after the summer break, so far, I think if you summed them up, in average, I think McLaren was the most competitive car.
"They are the ones which will be very competitive, no matter where we go, at least that's what the last couple of races showed. I think they still have a very good chance."