Arsenal are two points clear of second-placed Manchester City, who have two games in hand and will retake the lead if they beat West Ham on Wednesday.
Zinchenko, however, insists Arsenal still believe they can win the title after ending a run of four games without a win.
Mikel Arteta’s side cruised to a 3-1 victory at Emirates Stadium, thanks to two goals from Martin Odegaard and one from Gabriel Jesus.
They now have four games remaining this season, starting with Sunday’s trip to Newcastle.
Zinchenko said: “Now we have got three points, I hope the energy is back — and let’s see what is going to happen in the next games, because we have some tough games to play.
“Today’s win is so important for us to be back in a routine, for the mood in the dressing room and in terms also for our League position.
“Of course everyone was disappointed [after losing to 4-1 at Man City], but still we have a few games to play and everything is possible in this League.
“We need to keep fighting, because we worked so hard during this season. Unfortunately, [the title] is not in our hands, but you never know what can happen in this League.”
When Zinchenko joined Arsenal in the summer from Manchester City, he told his new team-mates they could win the title.
The left-back’s view has not changed since then, even though the Gunners started last month leading City by eight points and the title is no longer in their hands.
“Well, if you don’t believe, there is no point playing. So, of course I do [believe],” said Zinchenko.
“When I had just arrived, I said the quality everyone has here is incredible, the energy as well.
“So I said everything is possible in this life if we’re going to work so hard. And that’s what we’re trying to do.”
Arsenal blew Chelsea away in the first half on Tuesday night, with all three of their goals coming in a devastating 16-minute spell.
The Blues, who have now lost six games in a row under caretaker manager Frank Lampard, were off the pace and the only positive for them was January signing Noni Madueke scoring his first goal for the club.
“The team is back to its best,” said Arteta. “There was a lot of energy, determination, quality, movement, and we were really going for it.
“We wanted to prove we had that fire in the belly. I could see that in the last few days, and we prepared the game well.”
The only downside for Arsenal was defender Gabriel limping off in the second half with a knock after he had gone down in pain several times.
He will be assessed over the coming days, but Arteta will be concerned, as he is already without fellow centre-back William Saliba.
“We tried for 10 or 15 minutes, but he could not carry on, which is strange for Gabi,” said Arteta. “Normally he’s not one that wants to leave the pitch.”