Vettel has dropped from leading the title race to trailing Hamilton by 67 points in just seven grands prix, with his rival winning six of those and currently enjoying a four-race victory streak.
Hamilton can now seal the title at the next grand prix in the United States after Vettel hit Max Verstappen and spun in Japan, which limited him to sixth place.
When asked about the title being nearly over, Vettel said: “You say nearly.
“Obviously there is still a chance, the last couple of races we made it a bit too easy for them.
“But also credit to them, they executed well. That is the name of the game.
“We need to look after ourselves and do our bit for the next couple of races, and then we see.
“Surely it didn’t help when we finished sixth and they won the race.”
Sebastian Vettel, Ferrari looks at the rear Pirelli tyre of the car of Lewis Hamilton, Mercedes-AMG F1 W09 in parc ferme
Photo by: Mark Sutton / Sutton Images
Mercedes has enjoyed a qualifying advantage over Ferrari at the last three grands prix, although Vettel has been more competitive in race trim.
However, Ferrari’s botched strategy in Singapore cost him second there and he was not quite on terms with Mercedes in Russia.
In Japan, Ferrari’s tyre choice error and Vettel’s own mistake in qualifying set the tone for a miserable race at Suzuka.
Vettel feels he could have fought “at least one” of the Mercedes after battling from eighth to fourth on the opening lap, before undoing that work by colliding with Verstappen and dropping to last.
“It is very difficult to pass around here and follow up the hill, and with the fast corners that we have, but I thought that I could play with the car and make the tyres last reasonably well,” said Vettel.
“Obviously then we never know, because I had damage and in traffic and so on, but I was happy from my point of view with what I had in the race.”
Ferrari’s drop in performance has been stark, as it had emerged from F1’s summer break with its pace advantage over Mercedes from the first half of the season still intact.
Vettel said he had no explanation for Ferrari’s recent struggles.
“It has always been very close,” he said.
“I think the last races we were not as strong and I think the fact that we were better in the race was also due to the fact that they didn’t have to push, so you will never get the full picture.”
Pole sitter Lewis Hamilton, Mercedes AMG F1
Photo by: Steve Etherington / LAT Images
Following his Japanese GP win at Suzuka last weekend, Hamilton defended his rival over criticism of his recent errors.
“I feel the media need to show a little more respect for Sebastian,” Hamilton wrote on Instagram.
“You simply cannot imagine how hard it is to do what we do at our level, for any athlete at the top of their game that is.
“It is to be expected that being humans we will make mistakes but it is how we get through them that counts.”