The European champions made it three Barclays Premier League games without a win as Liverpool came from behind to snatch a 1-1 draw at Stamford Bridge.
That saw Chelsea end the weekend three points adrift of Manchester United at the top of the table in third place, a fortnight after they were bidding to go seven clear at the top.
Blues boss Di Matteo did not take kindly to the 10-point swing being pointed out, saying: "United came here, we had two sent off and they scored an offside winner. That's a big advantage for the opposition.
"We're still playing well and creating chances. We need to be a bit more clinical, to take our chances and finish the game off."
The Italian maintained his side were too good to suffer another bout of the winter blues, which has cost them dearly in three of the last four seasons.
"We're in much better shape than in previous years, in a much better position, and very close to our best," he said.
"If we had won today [Sunday], it would have been great for us.
"We're still in the mix. But the amount of games you play in this period has some kind of effect."
Chelsea wasted several chances to finish Liverpool off today [Sunday] and were almost made to pay the ultimate price when the visitors went close to completing their comeback.
"It was crucial to kill the game off," Di Matteo added.
"We had the chances to do that, but we missed opportunities, the goalkeeper made some great saves, and we didn't manage that second goal."
The loss of John Terry to a serious-looking injury did not help Chelsea, who conceded the equaliser from a corner.
Di Matteo suggested it should have been disallowed for a Suarez push on Ramires.
"It was a poor goal to concede," he said.
"We had our man marking the opposition and Ramires was with Suarez and he pushed him away to create that bit of space for himself to nod the ball in.
"Sometimes the refs notice, sometimes they don't. It's one of those."
Di Matteo insisted he had no intention of allowing Frank Lampard to leave in January amid reports the midfielder was set to quit for Chinese side Guizhou.
But he said Didier Drogba, who did leave Stamford Bridge for Shanghai Shenhua in the summer, would be welcome to train with his former club during China's off-season.
Liverpool boss Brendan Rodgers was delighted with his side's comeback, which made it six league games without defeat.
He said: "We were excellent second half. We were a wee bit tentative first half, and that was my fault.
"Great character from the players yet again. To come here, it's a terrific point."
A draw was not enough to lift Liverpool out of 13th place and they ended the weekend 15 points behind United. "Listen, the reality is we're a long way off in the league," Rodgers added.
"You don't need to be a rocket scientist to see the squad... These guys are giving me everything.
"We finished eighth last year. If we can improve on that, it'll be fantastic for us.
"That's the reality of where Liverpool are I'm afraid. But our young players will get better and better.
"We need one or two more players. That's our sixth draw, and a lot of those games we've come back into after going behind.
"But we need materials. If we can get one or two in January, we'll turn draws into wins."
Rodgers played down a knee injury to captain Steven Gerrard ahead of what was set to be the midfielder's 100th England cap.
"I think Steven will be all right," he said.
"He's opened up his medial ligament a bit and has some ice on his knee."
Jonjo Shelvey missed today's [Sunday] game with a thigh problem and Rodgers added: "He'll meet up with England, they'll look at him and we'll make a decision from there."