Chelsea can force themselves into the title race but Troy Deeney believes a glaring problem is “going to cost them” down the road.
Goals from Nicolas Jackson and Enzo Fernandez helped the Blues to their sixth win of the season as they beat Leicester City 2-1 in Saturday's early kick-off.
The result kept the Blues in third place but raised their points tally to 22, one behind second-placed Manchester City and six behind league leaders Liverpool, both with a game in hand.
Although ChelseaWith the Premier League season only 12 games old, Deeney felt the Blues, at the moment, are a guaranteed presence in the title conversation.
However, the former Watford striker said they will never take the next step towards becoming title contenders until a drastic change is made.
“Yes, they should be looking at (the title race) right now,” Deeney told talkSPORT.
“But I still think that the goalkeeper (Robert Sánchez) and the defenders continue to allow bad goals.
“That should have been an easy 2-0 win, if not a 3-0 win today. They just opened up behind today and I think that's why they have to go in the top four right now.”
“Unless they go out in January and get a couple of signings, that defensive line is going to cost them.”
If Chelsea heed Deeney's call for more signings in January, it would mean the Blues will increase their £197million summer transfer outlay.
A staggering 11 players came through the Stamford Bridge door in the summer, including goalkeeper Filip Jorgensen and centre-back Tosin Adarabioyo.
However, Jorgensen has had to settle for a place on the bench behind the starting no. 1, Robert Sánchez, while Adarabioyo has started twice in the Premier League this season.
But given that Chelsea finished sixth last season, the goal of finishing in the top four may be more appropriate than trying to convince themselves that they are in the title race.
They will also need to beat teams like Leicester comprehensively if they want to be seen as title contenders as well.
Leicester had lost two of their last three Premier League games and although they managed an expected goals (xG) figure of 1.11 to Chelsea's 2.64, Steve Cooper's side had their moments.
Kasey McAteer fired a shot just wide of the post in the first half, while Wilfred Ndidi missed an attempt inside the area.
However, Chelsea made the Foxes pay when it mattered most and, as Deeney pointed out, they should have scored more than two.
At the start of the second half, Cole Palmer looked like he was going to double the Blues' lead, but his low shot was blocked by Noni Madueke.
Madueke tried to jump away from Palmer's low blow but couldn't get his foot out of the way.
Maresca knows that his team cannot afford to lose many golden opportunities like that against better teams while tougher tests await in the top flight.
Speaking after the match, the Blues boss said: “For me (Jackson) is doing very well. Since we started, he is working hard with and without the ball.
“He is making the effort. Sometimes we use him as a midfielder or as an attacker, it depends on the game plan.
“We are very happy with Nico because of how he plays with the ball and especially without it. We are sure that he will improve.”
Regarding Malo Gusto and Pedro Neto, both absent from the matchday squad, Maresca added: “Malo was with us but during the night he didn't feel well.
“Pedro was a problem with the national team, there was an opportunity but we didn't take any risks. Hopefully he can be with us next week.”