Marquez, who will depart Honda for the Gresini Ducati team in 2024, made the remarks in the run-up to this weekend's Australian Grand Prix at Phillip Island, the scene of his only podium finish of the 2022 season.
Despite Phillip Island's reputation as a track where the rider makes more of the difference than the machinery, six-time premier class champion Marquez insists he is not at a level that would allow him to realistically harbour ambitions of winning.
He was similarly negative about his prospects of challenging for what would be a first grand prix victory since the 2021 Emilia Romagna GP at the remaining four venues on the 2023 schedule.
"To win this year will be difficult," replied Marquez when asked if he felt Phillip Island offered his last good opportunity to claim a victory aboard the RC213V.
"We cannot approach any race thinking about winning it because we are far. We are not one, two, three seconds behind the winner, we are seven or 10 seconds in our best race.
"We cannot think about winning here, Buriram or Valencia, which are the three best tracks [of the remaining five].
"In Malaysia and Qatar we will suffer a lot; these [other] three tracks we will suffer a bit less, but not so much less that we can think about the victory."
Marquez arrives in Australia off the back of a dismal weekend in Indonesia, where he crashed out of both the sprint race and main event.
The 30-year-old admits that he found Honda's struggles at the Mandalika track hard to accept after his podium finish in the previous race at Motegi, and that he will need to rebuild his confidence this weekend.
"This year it’s difficult to understand [beforehand] if our level will be good or not," said Marquez.
"At some race tracks where we didn’t expect to be fast, we were fast. In the past here I have been fast [at Phillip Island], but no expectations.
"I want to go out and understand [where the level is] in FP1. It’s true that I’m coming from a difficult weekend.
"We were coming from good shape [at Motegi] and then we arrived in a circuit where I struggled a bit more and I didn’t accept it. When you don’t accept it, you start to crash more than usual.
"In the sprint race I crashed on the first lap. Then in the main race I was calmer but even like this I crashed. This one cost me a lot of confidence, because I didn’t understand it. The one in the sprint race I could understand.
"Now I need to step back again and rebuild the confidence this weekend and we’ll see what we can do."