Antonio Conte says he will know whether Chelsea are title contenders after Christmas.
The Blues have hit a purple patch with four straight Premier League wins, scoring 11 goals in the process while conceding none.
The latest, Sunday's 2-0 victory at Southampton, came thanks to strikes from Eden Hazard and Diego Costa, a pairing that did so much to fire Chelsea to title glory two seasons ago.
But Conte has also sorted out the defence which let them down so often last term, having kept four clean sheets since reverting to a back three.
Victory meant Chelsea stay on the shoulders of the top three, just a point behind table-toppers Manchester City.
However, Stamford Bridge boss Conte said: "In this moment it's not important to look at the table. If you ask me a prediction of our championship now, it's very difficult to talk about.
"Now we must continue in this way. To stay close to first place is good, and gives us great confidence.
"I think game by game. I'm seeing a lot of positive things. Many games must pass before you can see whether you can fight for the title.
"Then you can see if you can stay up there in the title race. When you start the second part of the season, our ideas will be clearer."
Costa killed Saints off in the 55th minute with a superb curler after Hazard, reinvigorated following last season's misery under Jose Mourinho, opened the scoring with an angled drive after just six minutes.
Saints manager Claude Puel, whose side fell to their first home defeat of the season, gave Hazard his senior debut when he was in charge at Lille in 2007.
"I spoke with him after the game," he said. "He's come back perhaps after a difficult season at a good level, and when he plays with this level it's difficult, of course.
"He's a very good player, like Costa. They didn't have a lot of chances, but the chances they did have fell to those players."